Working with Big Ideas of Science Education - print version (2) (1).pdf

Working with Big Ideas of Science Education Edited by Wynne Harlen with Derek Bell, Rosa Devés, Hubert Dyasi, Guillermo Fernández de la Garza, Pierre Léna, Robin Millar, Michael Reiss, Patricia Rowell and Wei Yu Published by the Science Education Programme (SEP) of IAP www.interacademies.net/ac...

Working with Big Ideas of Science Education Edited by Wynne Harlen with Derek Bell, Rosa Devés, Hubert Dyasi, Guillermo Fernández de la Garza, Pierre Léna, Robin Millar, Michael Reiss, Patricia Rowell and Wei Yu Published by the Science Education Programme (SEP) of IAP www.interacademies.net/activities/projects/12250.aspx IAP - c/o ICTP campus - Strada Costiera, 11 - 34151 - Trieste - Italy www.interacademies.net [email protected] [ISBN no.] © Wynne Harlen 2015 Copies and translations may be made without fee or prior permission with due acknowledgement Working with Big Ideas of Science Education Preface Executive summary 1 1 Introduction and rationale 3 2 Principles 7 3 Revisiting big ideas: range, size and identification 11 Progression in developing big ideas 18 5 Working with big ideas in mind 34 6 Implementing big ideas 45 4 Introduction Rationale Challenges Benefits for individuals and society Range Size Identifying big ideas Concepts of progression Describing progression in big ideas Opportunities for all students Curriculum content Pedagogy Assessment Summary of implications Big ideas in national curriculum documents Teachers’ understanding of big ideas Formative evaluation of teaching for big ideas Concluding comment Participant profiles 53 List of related sources 57 WORKING WITH BIG IDEAS OF SCIENCE EDUCATION Preface In 2009 a group of experts in science education took part in an international seminar with the aim of identifying the key ideas that students should encounter in their science education to enable them to understand, enjoy and marvel at the natural world. An overcrowded and fragmented science curriculum was recognised as one of several factors in students’ perception that science was a disconnected series of facts of very little wider meaning. Part of the solution to this problem was to conceive the goals of science education, not in terms of the knowledge of a body of facts and theories, but as a progression towards understanding key ideas – ‘big ideas’ – of relevance to students’ lives during and beyond school. The seminar and subsequent work by the group resulted in the publication of Principles and Big ideas of Science Education, which was freely distributed, translated into several languages and received a good deal of interest across the world. Five years on, the initially identified reasons for a focus on developing big ideas in science remain but other reasons have emerged, adding to the compelling rationale. A second international seminar, attended by the same group of science experts, augmented by an expert on curriculum change, was convened to review the earlier work. The seminar, in September 2014, was funded by a generous contribution from the Ministry of Education of Mexico, for INNOVEC international collaboration activities, by contributions from the institutions of some of the participants and from some individuals. All participants took active roles in the two and a half day seminar and in subsequent review and refinement of this publication. A detailed record was kept of the seminar presentations and discussions. As before, the range of experience and cultural backgrounds of the members of the group will hopefully extend the relevance of the work for science education in different parts of the world. For this joint effort grateful thanks are due to the expert group: Derek Bell, Rosa Devés, Hubert Dyasi, Guillermo Fernández de la Garza, Louise Hayward, Pierre Léna, Robin Millar, Michael Reiss, Patricia Rowell, Wei Yu; and to Juliet Miller (rapporteur). EXECUTIVE SUMMARY Executive Summary The purpose of this publication is to update the discussion and conclusions about the essential understanding in science that all students should acquire during the compulsory years of school. It follows five years after Principles and Big Ideas of Science Education1 was written in response to concerns that many students did not find their science education interesting or see it as relevant to their lives. Part of the problem was an overcrowded curriculum that appeared to be a set of disconnected facts to be learned; thus part of the solution was to conceive the goals of science education, not in terms of the knowledge of a body of facts and theories, but as a progression towards understanding key ideas of relevance to students’ lives during and beyond their school years. These are identified as the ‘big ideas’ that should be understood by all students – not just those who go on to study science or take up science-based occupations beyond school – and equally by all, regardless of gender, cultural background or disabilities. Principles and Big Ideas of Science Education, resulting from an international seminar of expert scientist and science educators in 2009, identified some guiding principles, ten big ideas of science and four ideas about science and its applications. Working with Big Ideas of Science Education – resulting from a further seminar and work by the same group – adds to the earlier work in setting out in greater detail the rationale for working towards big ideas and the implications of this for curriculum content, pedagogy, student assessment and teacher education. As well as the continuing importance of factors relating to students’ and teachers’ perceptions of science, which prompted the initial work, several other factors can be identified relating to the potential benefits for students as individuals in an age of innovation and benefits for society. For individual learners there are benefits from being able to grasp the essential features of events or phenomena in the world around that enable them to make informed decisions affecting their own and others’ health and wellbeing. Society benefits from citizens making informed decisions about matters such as energy use and care for the environment. Science education also needs to take account of changes in the work place that require ability to link science with engineering, technology and mathematics (STEM), the urgent need for attention to major global issues such as the adverse impacts of climate change, the positive and negative influences of student assessment and the growing contribution of neurosciences to the understanding of learning. All of these add to the reasons for the development of big ideas to provide a framework for decisions about science education. Whilst the multiple goals of science education are recognised in the underlying principles, the focus here remains on conceptual understanding with the development of scientific capabilities and attitudes embedded in appropriate pedagogy rather than as separate lists 1 Principles and Big Ideas of Science Education Edited by Wynne Harlen with the contribution of Derek Bell, Rosa Devés, Hubert Dyasi, Guillermo Fernández de la Garza, Pierre Léna, Robin Millar, Michael Reiss, Patricia Rowell and Wei Yu. Published by the Association for Science Education, 2010. ISBN 978 0 86357 4 313. 1 WORKING WITH BIG IDEAS OF SCIENCE EDUCATION of goals. The big ideas of science and about science are expressed in the form of narrative descriptions of a progression that builds up understanding of key ideas across the years from the start of primary to the end of secondary school. The implication of putting into practice principles and big ideas are considered in relation to the selection of content, pedagogy, student assessment and teacher education. In relation to pedagogy it is argued that not only does inquiry have a central role in developing understanding but that identifying big ideas in science is a necessary accompaniment to promoting inquiry-based science education. A final section on implementation discusses what is needed to bring about change in practice, including how ideas are expressed in the science curriculum, developing teachers’ understanding of big ideas and evaluating teaching for big ideas. 2 1 INTRODUCTION AND RATIONALE 1 Introduction and rationale Introduction The five years since the publication of Principles and Big ideas of Science Education show evidence of the rapid changes taking place in education generally and science education in particular. Students are using digital technologies inside as well as outside the classroom; new frameworks for the curriculum are being implemented; computers are being used to extend the range of assessment; and there is further advance in understanding learning and how to bring it about. Even greater changes, with enormous implications for education, are taking place in the world of work, where technology has made certain types of work unnecessary. The opportunities for middle level labour are diminishing, leaving those occupations which are difficult to automate – mainly lower-level jobs and higher level work that requires uniquely human capabilities. For many, ability to create new products, solve problems and undertake complex tasks will – at least for the moment – be the route to avoiding unemployment with all its social consequences. Globalisation introduces opportunities but also challenges, particularly for those in parts of the world less able to change as rapidly as highly developed countries. To prosper in this modern age of innovation requires the capacity to grasp the essentials of diverse problems, to recognise meaningful patterns, to retrieve and apply relevant knowledge. Science education has the potential for helping the development of the required abilities and understanding by focusing on developing powerful ideas of science and ideas about the nature of scientific activity and its applications. Recognising this provides part of a strong rationale for revisiting the big ideas identified in 2009 and particularly the implications for change in science education practice required for their implementation. Finally, the global issues faced by humanity, such as climate change, health and population growth, create an urgent need for young people to have a basic understanding of the relevant scientific ideas, technological and ethical issues and powers of reasoning, to be prepared to face these issues. We now turn to review the rationale for the importance of identifying big ideas and note some associated challenges and benefits. Rationale Five years ago we identified these reasons for making explicit the core ideas that should be the goals of science education:  to respond to students’ perceptions of science as a fragmented collection of facts and theories of little relevance to them, by building ideas into a coherent picture of how the world works 3 WORKING WITH BIG IDEAS OF SCIENCE EDUCATION  to provide a basis for classroom activities that help students to explain things they find important  to provide a basis for selection from the enormous range of possible curriculum content  to inform the development of curriculum frameworks built on progression towards big ideas. These reasons continue to apply but now there are others to add, briefly discussed here but fleshed out in later discussion. They arise from three directions:  widespread embrace of inquiry-based pedagogy in science education  recognition of the connectedness of science and other STEM subjects2 in daily life contexts  greater understanding being provided by neuroscience of conditions that influence learning. Inquiry-based science education Inquiry-based pedagogy is being embraced in principle across the globe, supported in the last decade by an increasing body of research on its effectiveness. Learning science through inquiry involves learners developing understanding through their own mental and physical activity, starting from their existing ideas and, through collecting, analysing and interpreting evidence, developing more powerful and scientific ideas to explain new events or phenomena. It embodies a social constructivist view of learning and involves students working in ways that are similar to those of scientists, thus developing some appreciation of the nature of scientific activity. Although not all science learning can be or needs to be through inquiry, it has a key role in helping students to develop understanding. However, implementing inquiry effectively is time consuming and so there has to be a choice of those topics and activities that make best use of limited and precious learning time. The selection of the key powerful ideas that are more useful in understanding the world around is thus a corollary to seriously adopting an inquiry-based approach to teaching and learning in the compulsory years of school. Connections in daily life Situations where science is used in daily life, and which are likely to capture the interest of many students, often involve combining science with other subjects, particularly engineering, technology and mathematics. Changes in the workplace, and in research 2 Science, Technology, Engineering and Mathematics. We take the meaning of these to be: Science: the ideas about the natural world, warranted by empirical evidence, that have been accumulated over time and the processes by which these ideas have been generated. Technology: the systems, processes and artefacts produced by human beings to serve their needs or desires. Engineering: the systematic and iterative process, informed by scientific knowledge, of designing objects and systems to achieve solutions to human problems. Mathematics: the systematic study of patterns and relationships among quantities, numbers and space expressed symbolically in the form of numerals and forms and warranted through logical argument. 4 1 INTRODUCTION AND RATIONALE activity, increasingly require multidisciplinary/transdisciplinary teams to tackle a broad range of scientific and problems that may have implications for society. Real world contexts and problems – such as designing sustainable energy systems, bio-medical engineering, maintaining biodiversity in areas where conflicts arise between local and global needs – demand knowledge, concepts and skills from several disciplines. A general understanding of the issues and of their ethical implications is needed by all citizens if the political will is to be mobilised to solve the problems they present. These considerations raise questions of how to ensure relevant learning by all students, whether or not they will later be employed in such enterprises. It follows that being able to see the connections between different ideas in science, as in the understanding of big ideas and how they were developed, is an important part of preparation for work and life. Education that helps students to connect ideas across and within subject domains encourages creativity and innovation. It prepares students to participate in, rather than being at the mercy of, the rapid changes in occupations and communication using technologies developed through engineering and the applications of science. Neuroscience and research into cognition Advances in research into the activity of the brain are rapidly identifying factors that facilitate effective learning. A relevant finding is that ideas that are connected are more readily used in new situations than unconnected ideas. This provides support for working towards a few big ideas that enable understanding of the world and our experiences in it, rather than a series of disconnected items of knowledge. Building connections and recognising patterns enable learners to identify significant aspects when trying to understand new situations. Brain imaging reveals how grasping new ideas is accompanied by an emotional reaction showing that there is pleasure in developing understanding. Pedagogy that involves learning in groups and watching others who are more expert also finds support from identifying the activity of mirror neurons. While extravagant and unvalidated claims are sometimes made for the contribution of neuroscience to education, it does seem likely that more scientifically-based contributions will increasingly be forthcoming, with direct classroom applications not only to science education but to other subjects too. Challenges At the same time as acknowledging the strong case for focusing teaching on big ideas, it is important to recognise that some developments over recent years have created challenges, or indeed obstacles, to the changes that are needed for students to have the chance to develop understanding. Two key challenges concern student assessment and teacher education. Student assessment In many countries there has been a constant increase in testing and the use of test results to set targets for teachers and schools, in the false belief that this will improve learning. Conventional tests and examinations present a series of disconnected questions or problems, which all too often encourage teaching of disconnected pieces of knowledge. If progress towards big ideas is to be effectively supported and assessed there has to be a 5 WORKING WITH BIG IDEAS OF SCIENCE EDUCATION fundamental change in the ways in which data about what students are able to do are generated, collected and used. Without this, the impact of assessment on what is taught and how it is taught will restrain, even strangle, attempts to help students develop key abilities and understanding. Teacher education When planning lessons it is important for teachers to have in mind how the goals of individual lessons fit into a wider picture of more powerful ideas that can help students make sense of a broad range of related phenomena and events. Having this general direction of development in mind frames what teachers observe and look for in students’ actions, questions and talk, and will inform their decisions about feedback to students and how to adapt their teaching through formative assessment to support students’ further learning. This is particularly challenging for primary school teachers, who must teach all subjects, but equally for some secondary school teachers who teach all science domains but may have studied only one or two in depth. Many teachers’ own education in science at school lacked involvement in scientific activity and the opportunity of developing the big ideas. Teacher education should supply this experience if teachers are to be equipped to help students progress towards the goal of understanding these ideas. Benefits for individuals and society If we can meet these challenges there are important benefits for students as individuals and for society. Benefits for students derive from those of any well-designed programme of study. In science these include the satisfaction of being able to make sense of the world and appreciation of the nature of scientific activity and its impact on our lives. The added benefit from the development of powerful ideas which have wide application in a range of experiences follows from being able to grasp the essential features of events or phenomena even though lacking the knowledge of every detail. Understanding aspects of the world around helps individuals in their personal decisions that affect their health and enjoyment of the environment as well as their choice of career. The practice of questioning, seeking evidence and answers, and sharing views with others also contributes to building confidence and respect for themselves and others. Furthermore, the satisfaction of being able to see patterns in different situations and connections between them provides important motivation for learning during and beyond formal education. Benefits for society follow from young people developing understanding of key ideas that enable them to make informed choices both as students and later in life about, for instance, their diet, exercise, use of energy and care of the environment. As well as impact on their own daily lives, such matters have wider implications for their and others’ future lives through longer-term impact of human activity on the environment. Understanding how science is used in many aspects of life is needed for appreciating the importance of science and for recognising the attention that needs to be given to ensuring that scientific knowledge is used appropriately. Students need to know how, both currently and historically, the use of scientific knowledge in engineering and technology, can impact both positively and negatively on society. Education in science has a unique role in creating understanding and the will to tackle the issues that lead to inequalities in wealth, employment, health and education across the world. 6 2 PRINCIPLES 2 Principles Implied in the rationale for focusing on core ideas of science are certain principles relating to science education. Stating them explicitly makes clear the values and standards that have guided our decision about big ideas and about how to put them into practice. As a result of reviewing the principles identified in Principles and Big Ideas of Science Education we have found no reason to make any substantial changes in them. However, we concluded that it may be helpful to restate them here more briefly and as more clearly applying to particular aspects of science education. Principles applying to the aims of science education Throughout the years of compulsory schooling, schools should, through their science education programmes, aim systematically to develop and sustain learners’ curiosity about the world, enjoyment of scientific activity and understanding of how natural phenomena can be explained. Science education should provide every student equally with opportunities that enable them to take an informed part in decisions, and to take appropriate actions, that affect their own wellbeing and the wellbeing of others and the environment. It should aim to develop:  understanding of a set of big ideas in science which include ideas of science and ideas about science and its applications  scientific capabilities concerned with gathering and using evidence  scientific attitudes and dispositions. Science education should enhance learners’ curiosity, wonder and questioning, building on their natural inclination to seek meaning and understanding of the world around. Scientific inquiry should be introduced and encountered by school students as an activity that can be carried out by everyone including themselves. They should have personal experiences of finding out about and of making connections between new and previous experiences that not only bring excitement and satisfaction but also the realisation that they can add to their knowledge through active inquiry. Both the process and product of scientific activity can evoke a positive emotional response which motivates further learning. For learners as individuals, science education should help them to develop the understanding, powers of reasoning and attitudes that enable them to lead physically and emotionally healthy and rewarding lives. It should enable them as individuals and groups make more informed choices in relation to avoiding, for instance, waste of energy and other resources, pollution and the consequences of poor diet, lack of exercise and misuse of drugs. 7 WORKING WITH BIG IDEAS OF SCIENCE EDUCATION Through science education, students should develop understanding of big ideas about objects, phenomena, materials and relationships in the natural world. Science education should also develop big ideas about scientific inquiry, reasoning and methods of working and ideas about the relationship between science, technology, society and the environment. Although the big ideas of science (resulting from scientific activity) and about science (how we perceive and use science) form the main focus of this publication, the goals of science education should also include the development of scientific capabilities and scientific attitudes. Principles applying to the selection of learning activities Programmes of study should indicate a clear progression towards the goals of science education, based on current research and understanding of how learning takes place. Progression towards big ideas should result from study of topics of interest and relevance to the lives of students of all backgrounds. Diversity among students should be used to enhance the learning of all. Learning activities should enable students to experience science and scientific inquiry in accordance with current scientific and educational thinking. They should deepen understanding of scientific ideas as well as having other possible aims, such as fostering attitudes and capabilities. Students bring to school ideas formed about the world through their actions, observations and thinking in their daily lives. These need to be the starting points for the development of the understandings, capabilities and attitudes that are the goals of science education. Students of different backgrounds should have opportunities to learn from activities of interest to them and relevance to their experience. Progress towards goals should be informed by what is known about the direction and nature of that progress and particularly what students can be expected to know, understand, do and reason about at various points in the course of their school education. Learners find it very difficult to learn with understanding from tasks which have no meaning that is apparent to them. They learn more effectively when they can link new experiences to what they already know and are motivated by curiosity to answer questions. Activities should therefore enable students to engage with real objects and with real problems. Programmes of teaching and learning need to be sufficiently flexible to allow for differences in experiences and in what particular localities have to offer, so that students’ interests and questions are used as starting points in working towards common goals. Science should be experienced by students as aiming for understanding, not as a collection of facts and theories that have been proved to be correct. Scientific knowledge should be conveyed as a set of explanations for natural phenomena that are generally agreed to provide the best account of the available evidence. It should be recognised as the result of human endeavour involving creativity and imagination as well as careful collection and interpretation of data. 8 2 PRINCIPLES Principles applying to student assessment Assessment has key roles in science education and should in all cases ultimately improve learning. The formative assessment of students’ learning and the summative assessment of their progress must apply to all goals. Formative assessment should be used as an on-going part of teaching and learning to help students recognise the goals of an activity, judge the extent of their achievement of the goals and direct their effort effectively. Summative assessment, although more concerned with checking up and reporting on what has been learned, should be conducted in a way that supports further learning and avoids the negative impacts all too often associated with high stakes testing. Since what is assessed and reported is assumed to reflect what it is important to learn, it is essential that this is not limited to what can be readily tested. A range of methods should be used to gather and interpret evidence of learning so that students are able to show what they can do in relation to all types of goals. It should also be recognised that for various unavoidable reasons (such as being able only ever to sample achievement and other inherent short-comings of assessment instruments), the assessment of learning outcomes is always an approximation. Principles applying to teachers and schools Programmes of study for students, and the initial training and professional development of teachers, should be consistent with the teaching and learning methods required to achieve the multiple goals of science education. In working towards these goals, schools’ science programmes should promote cooperation among teachers and engagement with the community, including the involvement of scientists. Both initial and in-service teacher education should recognise that teachers as learners need to experience scientific activity and discourse at their own level. Courses should include opportunities to undertake different kinds of scientific inquiry, followed by reflection on the circumstances and the role of the teacher that supports understanding both of science and about science. Opportunities should also be created for teachers to work together and with the local community and particularly with the scientific community. The challenge of improving science education requires the cooperation of educators and scientists. Teachers should have opportunities to improve their own understanding in science, for example, through continuing professional development in which scientists take part and by sharing their expertise with each other in conferences and courses. Information about the applications of science can often be supplied by those engaged in local industries or in science-based activities in the community. Enabling science students in higher education or professional 9 WORKING WITH BIG IDEAS OF SCIENCE EDUCATION scientists to provide on-line help or visit schools to work directly with students to supplement their learning and help teachers with their subject knowledge, allows the science community to contribute to the improvement of science education and at the same time learn about pedagogy that is effective in science education at all levels. 10 3 REVISITING BIG IDEAS: RANGE, SIZE AND IDENTIFICATION 3 Revisiting big ideas: range, size and identification Science is complex. How can we expect students even to begin to understand the vast array of ideas, theories and principles that seem to be necessary to grapple with this complexity? A clue to how this might be possible comes from listening to experts in science explaining to non-experts how the world works. They identify the (usually very few) key ideas which explain a phenomenon, cutting through the distracting detail. For example, a physicist can show how just two key ideas (Newton’s second law and the universal law of gravitation) explain how satellites and space craft are kept moving round the Earth and enable us to calculate the velocities needed to keep these objects in orbit or bring them down to Earth. We are not suggesting the key ideas can be directly taught, or denying that building the relevant ideas involves bringing together many smaller ideas from a range of learning experiences. But we are convinced that ensuring that these learning experiences are linked to key ideas can provide the understanding that all students need to make sense of what they observe in the world. Moreover, as discussed earlier, this understanding can enable them to grasp what is involved in science-based decisions that affect their own and others’ wellbeing. Whether or not these potential benefits are realised will depend, of course, on the choice of ideas to be included. Two key decisions concern: Range – whether to include scientific attitudes and dispositions towards science and what are variously called skills, practices, competences or capabilities as well as core scientific ideas. Size – how broad a compass of phenomena the ideas should explain, recognising that the larger the idea, the more distant it is from particular phenomena and the more abstract it therefore appears to be. Range Science education is concerned with more than conceptual understanding, as expressed in the principles relating to aims (page 7). In addition to the ideas that explain what is going on in the world, science education has other aims, including developing:  understanding of the nature of science  the capabilities needed to engage in scientific activity  scientific attitudes and informed attitudes towards science  appreciation of the relationship of science to other subjects, particularly technology, engineering and mathematics. 11 WORKING WITH BIG IDEAS OF SCIENCE EDUCATION Whilst acknowledging that science education should lead to these various outcomes, our decision to focus on big ideas of science and about science follows from our view that ideas play a central role in all aspects of science education. The development of understanding is a common factor in all science education activities. Science inquiry capabilities, or practices, and scientific attitudes and dispositions are developed by engaging in activities whose content involves science understanding; otherwise the activities can hardly be called scientific. Although we may emphasise and reinforce behaviours relating to, for example, cautious attitudes to interpreting data, or what is needed to plan a scientific investigation, the activity will also relate to one or more scientific ideas, for these attributes are not developed in isolation from scientific content. This argument does not negate the value of establishing lists of attitudes and abilities and explicitly working towards them at the same time as developing some conceptual understanding, but it reflects the principle that all science activities should deepen understanding of scientific ideas as well as having other possible aims. Understanding the nature of science We also want learners to understand the processes of scientific activity as well as the ideas to which it leads, that is, to know how the ideas that explain things in the world around have been arrived at not just what these ideas are. Indeed, it is hard to envisage separating knowledge about scientific activity from knowledge of scientific ideas. Without knowing how ideas were developed, learning science would require blind acceptance of many ideas about the natural world that appear to run counter to common sense. In a world increasingly dependent on the applications of science, people may feel powerless without some understanding of how to evaluate the quality of the information on which explanations are based. In science this evaluation concerns the methods used in collecting, analysing and interpreting data to test theories. Questioning the basis of ideas enables all of us to reject claims that are based on false evidence and to recognise when evidence is being used selectively to support particular actions. This is a key part of using scientific knowledge to evaluate evidence in order to make decisions, such as about the use of natural resources. Capacity to engage in scientific inquiry Participation in scientific inquiry enables students to develop ideas about science and how ideas are developed through scientific activity. The key characteristic of such activity is an attempt to answer a question to which students don’t know the answer or to explain something they don’t understand. These may be questions raised by students but, since it is not realistic for all students always to be working on their own questions, it is part of the skill of teacher to introduce questions in a way that students identify them as their own. The answer to some questions can be found by first hand investigation, but for others information is needed from secondary sources. In either case the important feature is that evidence is used to test ideas and so the understanding that results will depend on what evidence is collected and how it is interpreted. Therefore, capabilities involved in conducting scientific inquiry have a key role in the development of ideas and the pedagogy that supports the development of big ideas must also promote the development of competence and confidence in inquiry. We return to this in Section 5. 12 3 REVISITING BIG IDEAS: RANGE, SIZE AND IDENTIFICATION The STEM context The question about the relationship between science, technology, engineering and mathematics (STEM subjects) arises because understanding situations in daily life often involves combinations of these subjects; indeed much of what is referred to as ‘science’ in everyday life is better described as technology or engineering. Greater integration of STEM in educational programmes would afford opportunities for a better match of teaching and learning to practices in the work place and research settings and would be more likely to capture students’ interest and engagement. A further argument for some degree of integration follows from the cognitive research that suggests connected knowledge is more readily applied in new situations than separate pieces of knowledge. However, what little research there is on the effects of integrating science with other subjects suggests that, at school level, it can be counter-productive to attempt to make connections if the ideas in each domain have not been securely learned. Rather than trying to teach the STEM subjects in an integrated manner, the advantages of bringing them together would be better secured by curriculum planning that coordinates related themes and topics. Size The issue of making connections across domains also arises in the context of addressing the question: how big should big ideas be? We identify big ideas of science as ideas that can be used to explain and make predictions about a range of related phenomena in the natural world. Explanatory ideas can come in different ‘sizes’: for any idea that applies to a few phenomena there is generally a bigger one applying to a larger number of related phenomena and which, in turn, can be subsumed into an even bigger, more comprehensive idea. For example, the phenomenon of one substance dissolving in another, such as sugar dissolving in water, is ‘explained’ by young children in terms of the sugar having disappeared. This naïve idea soon has to be adapted to account for the evidence that the sugar is still there in the water and then becomes ‘bigger’ to explain why some things do not dissolve in water and some colour the water but cannot otherwise be seen. Then, the idea of dissolving needs to be enlarged further to apply to other liquids and solids. This explanation might then be connected with how other phenomena are explained in terms of interactions at molecular levels. The process of connecting ideas together to form bigger ones could continue in theory until there is a very small number of overarching concepts or even a single one that explains everything. Such ideas would necessarily be highly abstract, distant from actual experiences, and less useful for explaining these experiences than ideas that are more obviously linked to particular events and phenomena. They do not merely cut across subject discipline boundaries, as do ideas described as interdisciplinary, but completely obscure discipline boundaries and are better described as transdisciplinary. They include ideas such as system, symmetry, causality, form and function, and pattern. Our decision to position big ideas at the interdisciplinary level, below the level of overarching transdisciplinary concepts, was taken by considering the needs of learners and their teachers. Discussing transdisciplinary ideas may be appropriate for the most able 18 year olds but otherwise is more appropriate for undergraduates and beyond. For the learner at school, who may or may not be embarking on a science-based career, the rather 13 WORKING WITH BIG IDEAS OF SCIENCE EDUCATION less general ideas with more obvious links to their experience seem most useful. It is the big ideas at this level that science education should aim to help all learners to develop, keeping in mind the difference between a statement of goals and how these goals are best achieved. Further breakdown into a range of smaller ideas is, of course, possible but risks losing the connections between the smaller ideas that enable them to merge into a coherent big idea. Identifying big ideas The approach to science education of working towards development of big ideas has been widely accepted, and indeed welcomed, in principle. In order to decide what changes, if any, were necessary in the ideas published in Principles and Big Ideas of Science Education we first reviewed the selection criteria that had been used. We concluded that they continue to apply, that is, that big ideas should:  have explanatory power in relation to a large number of objects, events and phenomena that are encountered by students in their lives during and after their school years  provide a basis for understanding issues, such as the use of energy, involved in making decisions that affect learners’ own and others’ health and wellbeing and the environment  lead to enjoyment and satisfaction in being able to answer or find answers to the kinds of questions that people ask about themselves and the natural world  have cultural significance – for instance in affecting views of the human condition – reflecting achievements in the history of science, inspiration from the study of nature and the impacts of human activity on the environment. Feedback on the resulting selection of big ideas has not pointed to a need for major changes but rather that it has stood the test of informal peer review. At the same time, it became clear that there is some way to go before the approach is manifested in classroom practice and teacher education. More attention needs to be given to how to work with big ideas in practice and the implications for curriculum content, pedagogy and student assessment. Consequently, even though we recognise that a different selection of ideas could be proposed, it was apparent that changes to the ideas at this stage, when they are beginning to be used, would not be helpful. Moreover, although not identical with the way in which ideas are presented in recently published curriculum frameworks, there are close similarities in the goals implicit in the curricula across many countries. For these reasons, having revisited the criteria used in selecting ideas and reviewed alternatives, we decided against making more than small changes of wording in the ideas identified and confirmed the selection of ten ideas of science and four ideas about science as before. The following list gives the brief summaries of the ideas that all students should have had opportunity to learn by the end of compulsory education. In Section 4 these ideas are expressed more fully in narrative form describing the progression towards them over the years of schooling. 14 3 REVISITING BIG IDEAS: RANGE, SIZE AND IDENTIFICATION Ideas of science 1 All matter in the Universe is made of very small particles Atoms are the building blocks of all matter, living and non-living. The behaviour and arrangement of the atoms explains the properties of different materials. In chemical reactions atoms are rearranged to form new substances. Each atom has a nucleus containing neutrons and protons, surrounded by electrons. The opposite electric charges of protons and electrons attract each other, keeping atoms together and accounting for the formation of some compounds. 2 Objects can affect other objects at a distance All objects have an effect on other objects without being in contact with them. In some cases the effect travels out from the source to the receiver in the form of radiation (e.g. visible light). In other cases action at a distance is explained in terms of the existence of a field of influence between objects, such as a magnetic, electric or gravitational field. Gravity is a universal force of attraction between all objects however large or small, keeping the planets in orbit round the Sun and causing terrestrial objects to fall towards the centre of the Earth. 3 Changing the movement of an object requires a net force to be acting on it A force acting on an object is not seen directly but is detected by its effect on the object’s motion or shape. If an object is not moving the forces acting on it are equal in size and opposite in direction, balancing each other. Since gravity affects all objects on Earth there is always another force opposing gravity when an object is at rest. Unbalanced forces cause change in movement in the direction of the net force. When opposing forces acting on an object are not in the same line they cause the object to turn or twist. This effect is used in some simple machines. 4 The total amount of energy in the Universe is always the same but can be transferred from one energy store to another during an event Many processes or events involve changes and require an energy source to make them happen. Energy can be transferred from one body or group of bodies to another in various ways. In these processes some energy becomes less easy to use. Energy cannot be created or destroyed. Once energy has been released by burning a fossil fuel with oxygen, some of it is no longer available in a form that is as convenient to use. 5 The composition of the Earth and its atmosphere and the processes occurring within them shape the Earth’s surface and its climate Radiation from the Sun heats the Earth’s surface and causes convection currents in the air and oceans, creating climates. Below the surface heat from the Earth’s interior causes movement in the molten rock. This in turn leads to movement of the plates which form the Earth’s crust, creating volcanoes and earthquakes. The solid surface is constantly changing through the formation and weathering of rock. 15 WORKING WITH BIG IDEAS OF SCIENCE EDUCATION 6 Our solar system is a very small part of one of billions of galaxies in the Universe Our Sun and eight planets and other smaller objects orbiting it comprise the solar system. Day and night and the seasons are explained by the orientation and rotation of the Earth as it moves round the Sun. The solar system is part of a galaxy of stars, gas and dust, one of many billions in the Universe, enormous distances apart. Many stars appear to have planets. 7 Organisms are organised on a cellular basis and have a finite life span All organisms are constituted of one or more cells. Multi-cellular organisms have cells that are differentiated according to their function. All the basic functions of life are the result of what happens inside the cells which make up an organism. Growth is the result of multiple cell divisions. 8 Organisms require a supply of energy and materials for which they often depend on, or compete with, other organisms Food provides materials and energy for organisms to carry out the basic functions of life and to grow. Green plants and some bacteria are able to use energy from the Sun to generate complex food molecules. Animals obtain energy by breaking down complex food molecules and are ultimately dependent on green plants as their source of energy. In any ecosystem there is competition among species for the energy resources and materials they need to live and reproduce. 9 Genetic information is passed down from one generation of organisms to another Genetic information in a cell is held in the chemical DNA. Genes determine the development and structure of organisms. In asexual reproduction all the genes in the offspring come from one parent. In sexual reproduction half of the genes come from each parent. 10 The diversity of organisms, living and extinct, is the result of evolution All life today is directly descended from a universal common ancestor that was a simple one-celled organism. Over countless generations changes resulting from natural diversity within a species lead to the selection of those individuals best suited to survive under certain conditions. Species not able to respond sufficiently to changes in their environment become extinct. Ideas about science 11 Science is about finding the cause or cause of phenomena in the natural world Science is a search to explain and understand phenomena in the natural world. There is no single scientific method for doing this; the diversity of natural phenomena requires a diversity of methods and instruments to generate and test scientific explanations. Often an explanation is in terms of the factors that have to be present for an event to take place as shown by evidence from observations and experiments. In other cases supporting evidence is based on correlations revealed by patterns in systematic observation. 16 3 REVISITING BIG IDEAS: RANGE, SIZE AND IDENTIFICATION 12 Scientific explanations, theories and models are those that best fit the evidence available at a particular time A scientific theory or model representing relationships between variables of a natural phenomenon must fit the observations available at the time and lead to predictions that can be tested. Any theory or model is provisional and subject to revision in the light of new data even though it may have led to predictions in accord with data in the past. 13 The knowledge produced by science is used in engineering and technologies to create products to serve human ends The use of scientific ideas in engineering and technologies has made considerable changes in many aspects of human activity. Advances in technologies enable further scientific activity; in turn this increases understanding of the natural world. In some areas of human activity technology is ahead of scientific ideas, but in others scientific ideas precede technology. 14 Applications of science often have ethical, social, economic and political implications The use of scientific knowledge in technologies makes many innovations possible. Whether or not particular applications of science are desirable is a matter that cannot be addressed using scientific knowledge alone. Ethical and moral judgments may be needed, based on such considerations as justice or equity, human safety, and impacts on people and the environment. 17 WORKING WITH BIG IDEAS OF SCIENCE EDUCATION 4 Progression in developing big ideas The development of understanding of big ideas in science is a gradual and progressive process continuing throughout formal education and beyond. It starts from the small, local and context-specific ideas that are formed through the study of particular phenomena. It involves both inductive and deductive thinking. Noticing patterns in observations may provoke questions about what is happening, but possible answers to these questions come from hypotheses drawn from previous experience, often involving a creative leap that connects previous to new observations. As learners use ideas from one event in explaining a related one their ideas become more useful in providing explanations that apply in several contexts. As ideas become less context-dependent they necessarily become more abstract. For each individual learner there is a progression from initial ideas specific to and formed from their early experiences to more powerful ideas that explain a wider range of related phenomena. There is a huge amount of research into students’ own ideas which shows that by the time they enter school they have formed ideas about aspects of the world and that many of their initial ideas are unlikely to be in line with scientific understanding. The path to more scientific ideas is unlikely to be the same for every individual since it depends on their experiences and on how they are helped to make sense of them. A description of progression – how ideas typically change over time – is important to inform curriculum development and the use of assessment both to help and to record learning. Most of all, however, it is important for teachers to see the connection between the learning experiences at various points in schooling and the overall aim of understanding big ideas. Conceptions of progression How are we to describe the progression of ideas from those that students form from their earliest years and bring to school to the grasp of big ideas we want them to have when they emerge from school? We found three main models of progression in ideas in the different ways in which learning goals are set out in curriculum frameworks. The first, commonly applied, implicitly identifies progression with climbing a ladder, where each step has to be completed before the next step can be taken. What is needed to complete each step is set out as learning targets. The size of the step varies in different models; it can be a year or several years or stages. This approach gives the impression of a fixed linear development with progression seen as a series of separate stages each with its own end-point but not necessarily linked to the understanding of the overall big ideas. If this happens then the purpose and relevance of their science experiences may not be conveyed to students. The second model is to describe only the overall end point, which can be reached in a variety of ways, rather as the pieces of a jigsaw can be put together in any order. This has disadvantages in providing too little guidance to teachers and other curriculum developers in deciding appropriate learning experiences. 18 4 PROGRESSION IN DEVELOPING BIG IDEAS The third model breaks overall goals into several strands. Ideas within each strand are gradually developed over time, often through a spiral curriculum. However, there is a risk of losing sight of connections between ideas in different strands that link them together in bigger ideas. Each model has advantages and disadvantages and something of each is probably needed since the nature and breadth of experiences required to develop them varies for different ideas. For instance, in some cases students’ own ideas lead them to different ideas for explaining essentially the same phenomenon encountered in different contexts. (For example, while they may explain that exposure to air and sunshine helps wet clothes to dry, they explain the disappearance of puddles in the road as the water leaking through the ground).The help they need is in making connections to see that a more scientific idea applies in each case (jigsaw). In other cases, students’ ideas are based on limited experience (‘all wood floats’) and this has to be extended in order to lead to a more widely applicable idea (spiral). Again, students’ reasoning is likely to be limited so that they may take notice only of evidence that confirms their idea or they retain an idea, despite contrary evidence, for lack of an alternative that makes sense, and which needs to be introduced (ladder). Describing progression towards the big ideas Our approach is to provide a description – a narrative – of how ideas change from the small ideas, to the big ones identified in section 3. The narrative fills in some ideas that are formed in the progress from the beginning ideas to the broad, more abstract ideas that enable understanding of objects, phenomena and relationships in the natural world (ideas 1-10). We provide the same kind of description of how these understandings are achieved, that is, ideas about science (ideas 11-14). Under each heading, where applicable, we begin with the small and contextualised ideas that children in the primary or elementary school, through appropriate activities and with support, will be able to grasp. These are followed by ideas that lower secondary school students can develop as their increasing capacity for abstract thinking enables them to see connection between events or phenomena. As exploration of the natural world extends in later secondary education, continuation of this creation of patterns and links enables students to understand relationships and models that can be used in making sense of a wide range of new and previous experiences. We have used a side bar to indicate the general range of ideas appropriate for different stages of schooling. Because there is so much variety in the way that phases of education are described in different countries we have labelled them in terms of ages, but using deliberately overlapping ranges since we do not intend to identify hard boundaries between what is appropriate at various ages. It is important to allow for diversity in the paths of cognitive development of individual students. What is important is the general direction of progress towards useful explanatory frameworks built on sound understanding at each stage. The ideas developed at all stages should be seen as contributing to this ongoing development. At each stage the aim is to move a little further towards a big idea, not to try to forge a link between every activity and the most sophisticated form of the idea. How far students can move in this direction at any time depends on a number of contextual variables, not least the pedagogy they experience, as discussed in Section 5. 19 WORKING WITH BIG IDEAS OF SCIENCE EDUCATION 11-14 7-11 5-7 1 All matter in the Universe is made of very small particles Atoms are the building blocks of all matter, living and non-living. The behaviour and arrangement of the atoms explains the properties of different materials. In chemical reactions, atoms are rearranged to form new substances. Each atom has a nucleus containing neutrons and protons, surrounded by electrons. The opposite electric charges of protons and electrons attract each other, keeping atoms together and accounting for the formation of some compounds. All the ‘stuff’ encountered in everyday life, including air, water and different kinds of solid substances, is called matter because it has mass, and therefore weight on Earth, and takes up space. Different materials are recognisable by their properties, some of which are used to classify them as being in the solid, liquid or gas state. When some substances are combined they form a new substance (or substances) with properties that are different from the original ones. Other substance simply mix without changing permanently and can often be separated again. At room temperature, some substances are in the solid state, some in the liquid state and some in the gas state. The state of many substances can be changed by heating or cooling them. The amount of matter does not change when a solid melts or a liquid evaporates. If a substance could be divided into smaller and smaller pieces it would be found to be made of very, very small particles, smaller than can be seen even with a microscope. These particles are not in a substance; they are the substance. All the particles of a particular substance are the same and different from those of other substances. The particles are not static but move in random directions. The speed at which they move is experienced as the temperature of the material. The differences between substances in the solid, liquid or gas state can be explained in terms of the speed and range of the movement of particles and the separation and strength of the attraction between neighbouring particles. The stronger the force of attraction between the particles the more energy has to be transferred to the substance to separate the particles , for example in going from the solid to the liquid state or from the liquid to the gas state. This is why substances have different melting and boiling points. 14-17 All materials, anywhere in the universe, living and non-living, are made of a very large numbers of basic ‘building blocks’ called atoms, of which there are about 100 different kinds. Substances made of only one kind of atom are called elements. Atoms of different elements can combine together to form a very large number of compounds. A chemical reaction involves a rearrangement of the atoms in the reacting substances to form new substances, while the total amount of matter remains the same. The properties of different materials can be explained in terms of the behaviour of the atoms and groups of atoms of which they are made. Atoms themselves have an internal structure, consisting of a heavy nucleus, made of protons and neutrons, surrounded by light electrons. The