This unit continues the work started in the first unit in Algebra I, but adds a narrowed focus on linear and exponential functions. Students investigate the rate of change and the initial value as key features that define functions. For the first time, students write equations that describe the relationship between quantities for linear and exponential functions. Whereas in Unit 1 much of the work is descriptive and general, Unit 2 asks students to calculate, quantify, and formalize their analysis and comparisons of functions.

**Essential Questions:**

- How do we measure change?
- How do we quantify the differences between representations?
- How do we quantify the relationships between quantities?