Personally, I would go with something like Jack Herer ( I think it's something like 55% sativa). A Haze blend would probably work well too. Since the key component would have to be the daytime element ( if you focus on the staying asleep thru the night aspect, you obviously aren't going to be of the mindset to study), I would think a sativa dominant strain would be the best fit. Bubblegum would be another option, if my memory is correct.