The mathematical purpose of this lesson is for students to recall how mean absolute deviation can be used to understand more about situations. In the associated Algebra 1 lesson, students will begin the change from using mean absolute deviation to the more mathematically useful standard deviation. Although the values of those measures of variability are different, interpreting their relative values is very similar.

The estimation Warm-up allows students the opportunity to make sense of problems (MP1), critique the reasoning of others (MP3), and model with mathematics (MP4). Students reason abstractly and quantitatively (MP2) when they compare situations using statistics and data displays. When students explain what they notice and wonder, they have an opportunity to attend to precision in language (MP6). Students make use of structure (MP7) when they notice similarities between box plots for a given situation.