Cobra Koans are a series of focused exercises centered around learning language features by correcting code whose assertions are failing.
As Laura @ DorkByte.com says: "Koans uses test driven development (TDD) or the notion of red, green, refactor. With the koans, run the tests and see it fail (red), make the test pass (green), then see if there’s any way you could improve upon it (refactor)."
You can find the koans at: https://bitbucket.org/CharlesEsterbrook/cobra-koans
There are only a few at this point in time. We need community members to contribute more koans.
Special thanks to Llewellyn Falco for getting this started.