Lesson objective: Apply multiplication and division of rational numbers to solve problems about rates of temperature change.

This lesson provides an opportunity for students to apply their knowledge and understanding of multiplication and division of rational numbers to a real-life situation. Students are asked to calculate the rate at which temperature changes as altitude changes and then apply this rate to a new situation.

Key Concepts students will use:

- The properties of numbers can be used to prove rules for multiplying with negative numbers.
- Real-life situations can be represented as quotients with negative numbers.

Skills students will use:

- Multiplying and dividing with negative numbers
- Solving problems with unit rates (Grade 6, Unit 2)
- Multiplying and dividing decimals (Grade 6, Unit 3)

Students engage in Mathematical Practice 2 (Reason abstractly and quantitatively) as they decontextualize and contextualize rational numbers by translating real-world rates of temperature change to numerical expressions and then interpreting their answers in the context of temperature change.

**Key vocabulary: **

- altitude

**Special materials needed:**

- none