[10-6]

shameless plug: I loved project euler and topcoder when I in high school. In 2011, there weren't really any nice, easy-to-use, interactive websites that allowed me to solve coding/algorithms challenges online easily, so that winter break my first year of college I made coderbyte.com for people to solve challenges online. Been running it ever since, but now there are like 20 similar websites as well.

[iandanforth]

Thank you! I love coderbyte. I especially love that you can immediately go back, correct your answer and get a perfect score. There is nothing more frustrating than a competitive screening tool that masquerades as an educational tool. Emphasizing mastery over getting it right on the first try is something that I deeply appreciate.

[tedmiston]

I haven't used Coderbyte yet, but I love the idea of going back and getting credit for showing what you learned / how you improved. (I mostly use Codewars which has a similar feature though.)

I've always wished academia worked this way. Seems logical to me. Everything else we do is iterative.