Build your problem solving skills.

My son uses this product. Looks like a pivot from a "math" version of Khan Academy.
Brilliant is like tumblr for math. You can post, solve, reshare and like problems. It covers topics such as algebra, combinatorics, number theory, SAT prep etc. As a former math major I love to do problems for fun. Brilliant is addictive. Great tool for kids learning math at all levels too.
anything that makes Math sexier for kids to do is awesome, but this is especially well done. it'd be great to have this for other school subjects too.
This is awesome! I was missing math and have been looking for this kind of game for a while. I'd love an app though. Great hunt @Nale :)
Thanks @SoleneMa :-) I want an app too! That way I could actually feel good about wasting time on my phone.