The big ideas that carry endless possibilities

Authored by science educator Wynne Harlen, Working with Big Ideas of Science Education provides a response to the concerns that the science curriculum in many countries is overloaded, over-detailed, over assessed and too distant from the inquiry-based approach that the subject requires.
Returning to the basics of why science is so enjoyable to teach and learn, Harlen and her fellow contributors express their aims for science education. This years report follows an earlier publication in 2010 by the same group of scientists, entitled Principles and Big Ideas of Science Education.
Helping students to build small ideas into bigger ideas promotes the recognition of links among ideas in different domains of science and between science and other subjects, particularly mathematics, technology and engineering – the STEM subjects.
Harlen said of the report: “It is vitally important that the education of all young people enables them to sustain their curiosity about the world we live in, enjoy scientific activity and develop a deep understanding of how events and phenomena around them can be explained, even though they may lack knowledge of every detail.
“This understanding is needed by all students – not just those who go on to study science or take up science-based occupations beyond school – and regardless of gender, cultural background or disabilities.”

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 an understanding through their own mental and physical activity.
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.

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 activity, increasingly require multidisciplinary teams to tackle a broad range of scientific 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.
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.

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 to the changes that are needed for students to have the chance to develop understanding. Two key challenges concern student assessment and teacher education.
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 encourages teaching of disconnected pieces of knowledge. If progress towards big ideas is to be effectively supported and assessed there has to be a 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 consider 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.

The aims of science education
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.
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 and about science form the main focus of this publication, the goals of science education should also include the development of scientific capabilities and scientific attitudes.
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.

Revisiting Big Ideas
Science is complex. How can we expect students to begin understanding the vast array of ideas, theories and principles that seem to be necessary to grapple with this complexity?
A clue as to how this might be possible comes from listening to experts in science explaining to non-experts how the world works. They identify the 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.
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.

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.

Engaging 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.

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.

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.
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 and 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.
Ideas should also 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, and have cultural significance 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.

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.
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.

Expressing big ideas of science
There are now examples of national curriculum documents that include overarching statements of aims expressed in the form of big ideas which are sufficiently similar to serve the same purpose. For instance, the guidelines being developed for the K-9 curriculum in France include knowledge that: ‘The Universe is structured from its biggest scale (galaxies, stars, planets) down to the smallest (particles, atoms and molecules)’.

But it is how such overall aims are broken down into goals for certain stages or years that is important in communicating the need for continuity and gradual progression in developing big ideas. Big ideas should run longitudinally through the description of learning goals across all stages. To convey the notion of progression in understanding it is not enough to state what is to be learned in terms of topics or concept words such as ‘force’, ‘electricity’ or ‘materials’. To be useful the statements should indicate the level of understanding or relationships and connections intended at particular stages.
Most curriculum documents, as well as setting out the concepts to be learnt, list science inquiry skills, or practices, to be developed at different stages. Usually these two types of outcomes are listed separately but some recently developed curriculum frameworks express goals at the end of stages, or years, as a combination of skills and concepts.
The framework for K-12 Science Education in the USA states outcomes in terms of ‘what students who demonstrate understanding can do’ as a series of statements which combine practices and overall concepts. Understanding ideas is to be developed through inquiry and investigation and, at the same time, that inquiry capabilities are developed and used in relation to scientific content.

However, although they are clearly not intended to restrict the combination of capabilities and content, there is some arbitrariness in the specified statements in relation to which capabilities and content are linked. Further, the complexity of the statements can obscure the relationship of the ideas at each stage to the overall big ideas.

Contributors to the report include: Derek Bell, Rosa Devés, Hubert Dyasi, Guillermo Fernández de la Garza, Louise Hayward, Pierre Léna, Robin Millar, Michael Reiss, Patricia Rowell, Wei Yu; and Juliet Miller (rapporteur).

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