This project will study how children and their teachers come to understand the invisible processes and mechanisms that underlie states and state changes in the water cycle. These studies are designed to test the effectiveness of a concept formation and explanation-based approach to learning and instruction. They also test the effectiveness of visual graphics and corrective feedback in learning difficult physical concepts that have multiple processes occurring simultaneously.

We know that explanation-based instruction increases understanding, learning, and retention of information. The structuring of text material in clear, explicit, causal, and explanatory ways is highly effective in achieving understanding and retention immediately and over the long term. The use of visual graphics in teaching about invisible physical processes, however, may be a critical variable for ensuring accurate understanding, above and beyond the coherence of a text. Receiving corrective feedback that compares the correct answer to an incorrect or incomplete answer may also be critical. The review of curricular materials used in elementary school science classes on this topic noted the clear absence of explicit concept definitions as well as explicit causal links that explained the relationships among many core concepts. Further, the explicit acknowledgement of ongoing parallel processes was never mentioned.

In contrast, our curriculum for the current studies provides explicit definitions of all the concepts, explanations of all the processes, and a focus on the unfolding of parallel processes. The curriculum was designed using an ideal end-state model of what it would mean for a student to have a correct and complete understanding of the water cycle. This model is used as a basis for assessments as well as instruction. The model is also used to suggest when and how graphics may be incorporated most effectively into instruction, as visual explanations of important, but invisible processes. The study will include students and teachers in Chicago public schools.

In the first two years of studies, 3rd and 4th grade teachers, 3rd and 4th grade students, and students from 7th and 12th grades will be pulled out for special instruction on these science units. Instruction will vary in terms of the amount and kind of feedback given to students to address misconceptions, whether students self-explain the materials out loud or not, and the presence or absence of static or animated visual graphics. In the third year, 3rd and 4th grade teachers who have first served as learners in our studies will then implement and teach the units in their own classrooms. The effectiveness of the new curriculum will be tested in two ways. In all three years, learning will be assessed via pre-post interviews and tests with students and teachers who receive different versions of the unit. We will also compare our students' performance to the performance of students who have not received our curriculum, but who have used other curricular materials like the FOSS system. Students will be compared on their knowledge of the water cycle and on their knowledge of general science concepts.