A Learning Cycle Approach to Introducing Osmosis

Abstract

HELPING students understand the nature of science and how to use scientific reasoning patterns have long been central goals of science education (e.g. American Association for the Advancement of Science [AAAS] 1928; 1989; 1990). However, in spite of a general and long-term philosophical commitment to these goals, the vast majority of research forces the conclusion that the goals have been largely unfulfilled. In our freshman level nonmajors course, lack of scientific literacy shows up in a number of ways, including student confusion regarding how to test tentative explanations and confusion regarding the similarities and differences among theories, hypotheses, laws and predictions. Indeed, in spite of our efforts, several students remain confused about the meaning of these terms during the entire semester. With the aim of reducing this confusion and helping students develop skills in generating and testing alternative explanations, we have developed several learning cycle-based inquiry labs that allow students to make observations, which in turn provoke the generation of causal questions. Once causal questions are raised, students generate and test several alternative explanations—all with minimal guidance from us. As you might imagine, this turns out to be no easy task for many students. Nevertheless, we believe that this is the best way to help students develop scientific reasoning skills and an awareness of the nature of science. Consequently, the purpose of the present article is to describe how we attempt to improve scientific literacy in the context of teaching about osmosis. We hope that you might try the approach to see how it works with your students. But if you do, expect a few rough spots. Experience suggests that many teachers and students alike need to develop new teaching and learning skills before success is attained. We will include hints about how to overcome some of the rough spots later. Most learning cycles, including the present one, include an initial ‘‘hands-on’’ instructional phase called exploration in which students explore new objects, events or situations. The exploration phase