Try half of a whole-wheat bagel (the Pepperidge farm ones are pretty good...at least I'm pretty positive they're Pepperidge farm

) with a tablespoon or so of peanut butter. I've found that this snack will keep hunger under control for a little while and not be one of those overly carb-laden (but usually delicious) snacks that puts me right to sleep.
Regarding the whole staying awake thing, yeah, I get sleepy, too. Sometimes, if you're really afraid you'll nod off, it might help to take yourself to a place that's a lot less likely to make you doze. For ex., when I'm at college, there are a couple of coffee shops right down the block. I go there because I can treat myself to a little drink as I study (which of course wakes me up) and I'm way less likely to fall asleep in the middle of Caribou Coffee than lying on my bed. When I am studying in my dorm room, blaring some fun music helps. Or sometimes, if I know I'm settling in for a long study session, I just ward off sleepiness in the first place by taking a 10 or 20-minute power nap.
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