Teaching and learning science with analogies

Most students bring a range of everyday experiences and a rich sense of curiosity to learning in science. They come asking how cells grow and divide, why two equal and opposite forces continue to act when a book sits on a table and why indicators change colour in acids and bases. With their desire to explore these questions they also bring their personal ideas of what counts as knowledge, commitments and preconceptions and intuitive knowledge. These elements in their conceptual background are the bricks and mortar from which you, the teacher, help them build new scientific knowledge. But student conceptual backgrounds are also the source of many folk explanations and alternative conceptions. ... And so, in a constructivist classroom, the challenge is how to employ the sutdents' prior knowledge, experiences and preferences in ways that develop scientifically acceptable ideas without confusing and discouraging them. Working scientifically is a constructivist approach that encourages students to ask questions, design experiments, collect and interpret data and communicate their findings to their peers and interested adults. But inquiry learning (or investigating, understanding and communicating) is not discovery learning because the teacher plays a key role in the learning performance. Left to their own devices, students cannot investigate and explain scientific concepts like floating and sinking, chemical reactions and blood circulation. Our aim is to place as much of the planning, experimenting and explaining that the students are capable of in their hands and minds. So, what do we do when we see the blank looks on students' faces or hear them confusing scientific terms and ideas? Experienced teachers do know what to do when such problems arise: they provide the 'need to know information', ask probing questions or suggest an experiment and sometimes provide an analogy or model.