# Fighting Fleas

## Exponential Decay

Use for CMP2 and CMP3, Problem 4.2 Fighting Fleas

The students move to decay factors that are expressed in percents and learn to distinguish between growth factors and growth rates. The focus is on evidence of student understanding, and the teacher's role in assessing understanding and adding value to the Summary phase.

The vieo concludes with the teacher reflecting on the lesson.

Real time is about 55 minutes.

As you view the video, consider the following:

- What is the evidence of students’ understanding and reasoning? What prior understandings do you see students using or building upon?
- What is the evidence of students’ understanding and reasoning? What prior understandings do you see students using or building upon?
- What is the evidence of students’ use of the mathematical practices from the Common Core State Standards? To what extent are students growing in their sophistication of their use of the practices?
- Were there any “aha moments” in the video?
- How is the teacher facilitating the development of students’ understanding and reasoning?
- As a teacher, how would you use the information from this lesson to plan the next lesson?

Full Length (22:24) or Video Clips by Chapter (length varies)