Reasons for use of videos from "Talking about rates".

1. See an example of how a teacher's insensitivity to how a student is thinking derails the best of intentions with regard to teaching for powerful understanding of an idea.
   
   
2. See an example of remedial instruction that focuses on the underlying causes of a student's difficulties instead of trying to repair her procedural knowledge.
   
   
3. Allow you to reveal their thinking with regard to these issues. That is, the conversations hopefully will provide insights into how you think about teaching in relation to learning, and provide insights into your thinking about the importance of being guided by a model of learning.
   
   
4. Provide an occasion to begin talking about "the logic of the lesson".