Geometry Lesson — Intro to Euclidean Geometry
Overview
A concise lesson covering basic Euclidean geometry: points, lines, planes, angles, triangles, congruence, similarity, parallel/perpendicular lines, circle basics, and key theorems with worked examples.
Problem: The lesson is missing a file (404 error).
Look for "P5.js" or "Three.js" in the URL
The best lessons use these libraries. If the page loads slowly or looks like a 1990s Geocities site, move on. Look for clean UIs with WebGL.
Step 4: Publish
Commit the file and push to GitHub. Go to your repository Settings > Pages. Set the branch to main and save. Your lesson will be live at https://yourusername.github.io/geometry-lesson/.
Because these sites are hosted on GitHub, they are completely free, open-source, and accessible from any device with a browser.
- Zero Cost for Hosting: Teachers can create a semester’s worth of visualizations without paying for a server.
- Version Control: You can track changes to a lesson. If an interactive model breaks after an update, you can revert to a working version.
- Community Collaboration: A teacher in Brazil can improve a lesson created by a teacher in Canada via pull requests.
- No Installation Required: Students click a link; they are instantly in the lesson.
3. Interactive Controls
- dat.GUI – sliders for angles/lengths
- Paper.js – vector graphics with mouse interaction
- React + SVG – dynamic geometry problem generators
- Relevance: This type of paper explores how platforms like GitHub allow teachers to share "Geometry Lessons" (code and HTML) freely. It argues that GitHub.io acts as a free Learning Management System (LMS) for math teachers.
