Based on extensive research, this curriculum reveals to the teacher a sequence of intermediate models (learning pathway) that the teacher helps the students construct while learning about human respiration. The students originate these intermediate models by successive revisions and modifications of their prior models. However, these changes are stimulated by appropriate strategies used by teachers in a certain order and in a determined position. To help teachers more fully understand and use the strategies designed into the Energy curriculum, we have developed a series of short video clips that are found on the accompanying CD. Throughout the video clips you will see real teachers and real classrooms using the various strategies to construct understanding. Each strategy will be accompanied by a video clip, discussion, and questions for you to ponder. We hope that this aids in your understanding of the curriculum.

Many different teaching strategies were carefully examined and coordinated to stimulate the students in revising and modifying their prior models. For instance, when the students have gaps in their models the teacher may use an analogy to help them fill in the gap. On the other hand, when the students have more information about the topic but it is not in agreement with the target concept, the teacher may use a strategy to encourage the students to criticize their prior model and to determine whether it makes sense. For instance, the teacher may use strategies such as discrepant questioning, discrepant events, hands on activities (labs), thought experiments, and animations.

Strategies are also used to help students to reason throughout the criticism and revision process. These include such strategies as drawing, questioning, hands on activities, and model competition.

In this section, we will examine more carefully each of them since they constitute the "tools" that foster the students' reasoning. For examples of these strategies along with instructions on how to use them, please view the video clips on the CD.