Brilliant.org

Brilliant - Understand concepts and build your problem solving skills with thousands of free problems and examples in math, science, and engineering.

Master concepts by solving fun, challenging problems. We’ll help you learn real math and science through conceptual quizzes that are both entertaining and educational.

With free Problems of the Week, you can solve and discuss fascinating problems with members around the world. If you enjoy these problems, then it’s time to subscribe. Once you do, you’ll have access to courses with hundreds of guided exercises on everything from logical reasoning to artificial neural networks.

Brilliant is designed for: Student enrichment: Feed your hunger to learn Recreational learning for adults: Hundreds of interesting topics to choose from Professional development: Keep your problem solving on the cutting edge