Lesson objective: Use the Mean Absolute Deviation to compare two datasets.

This lesson provides an opportunity for students to apply their knowledge and understanding of mean absolute deviation to a real-life situation. Students are asked to determine if a greater mean indicates a greater variation in the data.

Key Concept students will use:

- The variation (or spread) in a data set can be described by the mean absolute deviation, which describes how far data points are from the arithmetic mean.

Skills students will use:

- Finding measures of center
- Calculating the mean absolute deviation

Students engage in Mathematical Practice 3 (Construct viable arguments and critique the reasoning of others) as they determine that Omar's reasoning is incorrect even though his conjecture is correct.

**Key vocabulary: **

- mean
- mean absolute deviation
- measure of variation

**Special materials needed:**