Well, there are several "sugar substitutes" I have found in college that fulfill these cravings, and also keep my body in it's healthy state.

I had never been a big mango fan as a child, but a good friend of mine let me try one of his dried mangoes while I was in high school. To my surprise, the dried mango's did not have the funny after taste of regular mangoes, and were a little sweeter. Besides the fact that they are not messy, the dried mangoes are a perfect sugary substitute.
Trader Joe's Power Berries
Peanut Butter
I think it is disgusting usually when people eat straight out of the peanut butter container, but when class is starting in 15 minutes and you need a quick sugary fill, the peanut butter does the trick. One, it has good fat for your body. Two, it is pretty sweet so it will hold anyone over for a while.
Chocolate covered raisins
These are similar to the power berries, except even better. You know why!? because they come in milk chocolate, dark chocolate, and white chocolate! These travel easy, and are usually fresh if you get them at a large grocery store. (At least I think the bins they are sold in are fresh ;)) In any case, they are sweet as any sugary treat you could think of, and who doesn't want to eat raisins without having to actually taste them!?
Yogurt
I know you have seen them, you know, the yo plait commercials where people are talking about the yummy desert they are having, but it is actually yogurt. Well, I am not sure how I feel about eat yogurt that is supposed to taste like a red velvet cake,but strawberry banana amongst other flavors are great sugary substitutes.
Frozen or Dried Cranberries
I had not thought of this until I had a conversation with my roommate, who is in fact a boy, and told me he eats frozen cranberries to settle his cravings. It is like ice cream, minus the cream and the sugar, and all of the other things in it we can not pronounce.