Learning goals: Teacher Facing Calculate the mean absolute deviation (MAD) for a data set and interpret what it tells us about the situation. Compare and contrast (in writing) distributions that have the same mean, but different amounts of variability. Comprehend that “mean absolute deviation (MAD)” is a measure of variability, i.e., a single number summarizing how spread out the data set is. Full lesson plan (warm-up, activities, synthesis, cool-down prompt) from 6.8 Data Sets and Distributions, Grade 6.