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A framework for building exercises to work with Khan Academy.
HTML JavaScript CSS Python Shell Makefile

Fix comparing_fractions_1 freezing issue again.

I was horribly misled! I found this bug on Monday but Ben Eater told me it was
fixed by Marcia's commit D19680. I should have looked more closely at that
commit, because it turns out that change didn't fix the bug =(

Test Plan:
Load the exercise /e/comparing_fractions_1
Do a bunch of problems to satisfy myself that both problem types work now.

Reviewers: marcia, eater

Reviewed By: eater

Differential Revision:
latest commit 89cb60f077
@tomyedwab tomyedwab authored
Failed to load latest commit information.
build Add new exercise colors to KAthJax and Math.js
css Ensures that the "Show scratchpad" button works
exercises Fix comparing_fractions_1 freezing issue again.
fonts Move all answer area content to the bottom of the question area
genfiles Remove references to `USERNAME`
images Update badge images and fix clipping
local-only Upgrade katex in to v0.2.0
test Tests: Make tests run again
third_party Add new exercise colors to KAthJax and Math.js
tools Add tools/, which will be automatically run by khan-linter.
utils Improve hints for comparing fractions exercises
.arcconfig Fix the Show Answers button when reporting an exercise issue.
.arclint add default .arclint file
.gitignore Fixed a few TODOs.
.gitmodules Move qunit to a more-global directory
.travis.yml Try a different room ID!
Makefile Get rid of an obsolete comment. Link to careers page, not Jobvite
exercises-stub.js (khan-exercises) Replace top-level var declaration with explicit glob…
history.js Fix coach report answer correctness color
interface.js Revert "Removing gandalf bridge"
khan-exercise.js Fix the Show Answers button when reporting an exercise issue.
lint_blacklist.txt Use webpack to bundle JS together, not requirejs
main.js Use requirejs for module loading
package.json Rewrite pack.rb in javascript, to remove the main ruby dep on our cod…
requirements.txt First pass at creating a new script for our i18n e…

Khan Academy Exercises

Copyright (c) 2014 Khan Academy

The exercise framework is MIT licensed.

The exercises are under a Creative Commons by-nc-sa license.

Exercise Framework

Khan Academy has created a generic framework for building exercises. This framework, together with the exercises themselves, can be used completely independently of the Khan Academy application.

The framework exists in two components:

  • An HTML markup for specifying exercises.
  • A jQuery plugin for generating a usable, interactive, exercise from the HTML markup.

Using the Framework Locally

You need to serve the files from some sort of a server. You can't just open the files directly in a browser. For example:

cd khan-exercises
python -m SimpleHTTPServer # or python3 -m http.server

Now if you open your browser to http://localhost:8000 (or you should see the contents of the khan-exercises directory. Navigate to the exercises subfolder, and an HTML file under there to see an exercise.

Exercise Development

This framework supports over 450 of our current math exercises including updated versions of many exercises Sal built for his cousins before he made his first video! New exercises on Khan Academy, however, are now written by many content experts using Perseus and stored in our datastore as individual questions.


If you're passionate about providing a free world-class education for anyone, anywhere and want to apply to be a full-time or intern software developer at Khan Academy, please do so.

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