I'm referring to the ability to learn and retain material, doesn't have to be in a classroom. So I don't think that whether you're reading, being lectured, etc. would impact whether the time of day affects you. As for being creative, I imagine the same arguments for mornings being more productive would apply (better physiological state).

I have a feeling you might enjoy "The One World Schoolhouse" by Salman Khan (as in Khan Academy).