Lesson objective: Apply understanding of proportional and non-proportional linear functions and their components to a situation where proportional and non-proportional data must be sorted and modeled.

This lesson provides an opportunity for students to apply their knowledge and understanding of proportional and non-proportional linear relationships to a real-life situation. Students are asked to sort through scrambled paychecks to see which ones could be for an employee that is paid hourly, and which ones could be for an employee paid a daily rate plus a payment per tour, then calculate the next payment for each.

Key Concept students will use:

Skills students will use:

- ability to classify linear relationships as proportional or non-proportional
- calculation of rate of change (or constant of proportionality)
- calculation of initial value

Students engage in Mathematical Practice 1 (make sense of problems and perservere in solving them) as they use their knowledge of proportional and non-proportional linear relationships to try to decipher the information that was provided in the task, and develop a strategy for making use of it.

**Key vocabulary: **

- constant of proportionality
- initial value
- non-proportional
- proportional
- rate of change