1. Learners must construct their own personal understanding of each topic.

2. Learners can more easily engage in sense-making activities if they begin by considering concrete, real, familiar experiences before abstract.

3. Learners readily construct their own ideas, some of which are valuable and some of which are contrary to scientific thinking.

4. Learners have a confirmation bias. They tend to look for confirming evidence and deny/ignore disconfirming evidence. (Brewer & Chinn, 199 )

5. Learners have limited attention spans.

6. When learners practice activities that are authentic to the discipline, it is likely that they will be better able to perform in that discipline.

7. Learners benefit from opportunities to use and apply their knowledge and skills in a variety of contexts.

8. Science learners are encouraged to develop evidence-based (case-based) reasoning to support or refute their scientific ideas. (How do I know? Why do I believe?)

9. Learners need practice in deciding when it is appropriate to use particular knowledge and skills and how they may best be employed in a given situation.