I got back from China two days ago and I'm still very jet lagged but I have classes today (college, first day of classes for the spring semester). I have three classes in a row this afternoon from 1pm-5:35pm with only a ten minute break between each class. I need a way to stay awake, but I can't have caffeine. Any suggestions? Please help!

Also, tips for getting rid of jet lag are welcome as well. First, just help me stay awake for class today!