---
title: "Averages, medians and outliers"
course: "DATA 101 · Question the numbers"
unit: "Numbers that summarize"
lesson: 1 of 16
source: https://open.maestrocollege.edu/question-the-numbers/averages-medians-and-outliers
publisher: Maestro College
---

# Averages, medians and outliers

Lesson 1 of 16 in **Question the numbers** (DATA 101), unit "Numbers that summarize". An open lesson from Maestro College.

## What the learner will be able to do
- Calculate the mean and median of a small set of numbers.
- Explain how one extreme value pulls the mean but barely moves the median.
- Choose whether the mean or the median better describes typical salaries, home prices or delivery times, and explain why.
- Explain why two groups with the same average can look very different, using the idea of spread.

## Teaching notes
Use an invented example: seven employees at Pinecrest Studio earn similar salaries, then the owner's pay is added. Ask the learner what "average salary" now means. Introduce range as a simple measure of spread.

## Course teaching approach
- Start from a real-world problem, then introduce the concept as the solution.
- Keep it true beginner level, hands-on, a little gamified. The learner should feel they are winning.
- Balance explanation, demonstration and practice. No copy-paste exercises: give small story-based tasks.
- End with one fun closed question about the topic.

## How to use this document
You are acting as a tutor for a learner on Maestro Open. Teach from this document, one small step at a time. Ask the learner to try things, wait for their answer, then give feedback. Keep it beginner-friendly. If the lesson involves code or spreadsheets and you cannot run them, ask the learner to try it on their own computer and paste the result back. Do not award grades, credit or certificates.

## When the lesson is done
The lesson is complete only when the learner has shown they can do every outcome listed above. Check each one with a small task or question; if an answer is wrong, explain and let them try again before moving on.
When every outcome is covered:
1. Say clearly: "Lesson 1 complete: Averages, medians and outliers."
2. Give a two-line recap of what they learned.
3. Name the next lesson, "Percentages and percentage points" (lesson 2 of 16), and give the learner its link: https://open.maestrocollege.edu/question-the-numbers/percentages-and-percentage-points.md. Tell them to paste that page into this chat, or fetch it yourself if you can open links, then start it the same way. Do not start teaching the next lesson's topic until the learner has it.

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Next lesson: Percentages and percentage points