---
title: "Insertion sort (vs. bubble)"
course: "PY102 · Think like a programmer"
unit: "Searching and sorting"
lesson: 38 of 40
source: https://open.maestrocollege.edu/think-like-a-programmer/insertion-sort-vs-bubble
publisher: Maestro College
---

# Insertion sort (vs. bubble)

Lesson 38 of 40 in **Think like a programmer** (PY102), unit "Searching and sorting". An open lesson from Maestro College.

## What the learner will be able to do
- Recognize insertion sort as repeatedly inserting each element into its correct position.
- Recognize that insertion sort runs in quadratic time, O(n^2), on average but is near O(n) on nearly sorted data.
- Compare bubble and insertion sort by how they scan and move values, recognizing both are O(n^2) for large lists.

## Teaching notes
* The lesson includes an explanatory, highly important VIDEO that plays a central role in delivering the material. Use it and keep in mind that once the student watches it, they should already grasp a significant part of what the lesson aims to teach.
* Start the lesson with a short explanation of the concept, then show the video once the learner has basic context, keeping it early in the session.

## 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 38 complete: Insertion sort (vs. bubble)."
2. Give a two-line recap of what they learned.
3. Name the next lesson, "Sorting with Python tools" (lesson 39 of 40), and give the learner its link: https://open.maestrocollege.edu/think-like-a-programmer/sorting-with-python-tools.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.

Previous lesson: Bubble sort
Next lesson: Sorting with Python tools