The mathematical purpose of this lesson is to estimate the population mean with an associated margin of error using sample means from random samples. The work of this lesson connects to previous work because students used sample proportions from random samples to estimate a population proportion and an associated margin of error. The work of this lesson connects to upcoming work because students will use a randomization experiment to compare two treatments. When students make connections between estimating the margin of error for population means and for population proportions they are looking for and making use of structure (MP7).
Lesson overview
 12.1 Warmup: Rolling Distribution (5 minutes)
 12.2 Activity: Rolling for Means (15 minutes)

12.3 Activity: Margin of Error for Means (15 minutes)
 Includes "Are you Ready for More?" extension problem
 Lesson Synthesis
 12.4 Cooldown: Streaming Games (5 minutes)
Learning goals:
 Determine (in writing) an estimate for the population mean with a margin of error using sample means from random samples.
Learning goals (student facing):
 Let’s estimate population means using sample data.
Learning targets (student facing):
 I can calculate the mean and standard deviation of sample means and use the information to estimate the margin of error.
 I understand that sample means that are normally distributed follow the same pattern as sample proportions.
Required materials:
 Number cubes, or access to devices that can run the GeoGebra applet.
 Statistical technology
Required preparation:
 Each student will need a number cube or alternatively, devices that can run the GeoGebra applets for the Rolling for Means activity.
 Acquire devices that can run GeoGebra (recommended) or other spreadsheet technology.
 It is ideal if each student has their own device. (A GeoGebra Spreadsheet is available under Math Tools.)
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