Something to think about....
Yet sleep does play a key role in learning. It's during sleep that we consolidate, organize, and file what we've learned. Deprive yourself of sleep and you lose about 30 percent of what you've learned that day and two days earlier.
What's more, researchers at Stanford University have found that students who stay up two hours later than usual the night before a test tend to score lower on that test even if they've spent the extra hours studying.