Really nice! When I was in college we had all sorts of online systems that automatically graded assignments based on how close to the correct answer your supplied answer was. I think it'd be nice if in the future there was more of an overlap between science classes and programming classes (almost like a freshman / junior level scientific computation class) where instead of approaching problems from a pure theoretical perspective, we involved these types of computational approaches in parallel. Personally I have found that while I often know how to perform various theoretical computations, it's faster for me to just throw together a quick script to approximate the result (e.g. what's the expected value of the product of two gaussians?)