Lesson 5: Calculating Measures of Center and Variability
About this lesson
This lesson is optional because it revisits below gradelevel content. If the preunit diagnostic assessment indicates that your students know how to calculate the mean, median, mean absolute deviation (MAD), and interquartile range (IQR) then this lesson may be safely skipped. This lesson connects to upcoming work because students will interpret data using measures of center and measures of variability throughout the unit, so it is important that they understand what these statistics mean. When students explain the MAD using the meter stick example they are engaging in MP2 because they were reasoning abstractly and quantitatively by interpreting the MAD in context.
Lesson overview
 5.1 Warmup: Calculating Centers (5 minutes)
 5.2 Optional Activity: Heartbeats: Part 1 (10 minutes)

5.3 Optional Activity: Heartbeats: Part 2 (15 minutes)
 Includes "Are you Ready for More?" extension problem
 Lesson Synthesis
 5.4 Cooldown: Calculating MAD and IQR (5 minutes)
Learning goals:
 Calculate mean absolute deviation, interquartile range, mean, and median.
Learning goals (student facing):
 Let’s calculate measures of center and measures of variability and know which are most appropriate for the data.
Learning targets (student facing):
 I can calculate mean absolute deviation, interquartile range, mean, and median for a set of data.
Required materials:
 preprinted slips, cut from copies of the blackline master.
Required preparation:
 You will need a meter stick and 14 pennies (or other small weights) for a demonstration.
 An optional blackline master is included as a graphic organizer for computing interquartile range.
 One copy of the blackline master contains 2 graphic organizers.
Standards:
 This lesson builds on the standard: CCSS.6.SP.B.5.cMS.6.SP.5cMO.6.DSP.B.5c
 This lesson builds towards the standards: CCSS.HSSID.A.1MS.SID.1CCSS.HSSID.A.2MS.SID.2MO.A1.DS.A.1MO.A1.DS.A.2
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