Dreams are not predictors of the future, however, your dream could be an indication of what you are feeling. Your dream could be that you are thinking of moving on, that you like this other person, etc.
So in a sense, yes your dream could come true - he could ask you out. If you want to help your dream along, why not go talk with the boy. If you do not feel confident enough to ask him out, just simply talk with him - it seems you know him a bit sometimes just showing you are interested by saying Hi what did you think about math class today - boring huh....might help give him confidence to talk a bit more to you.
Worst thing - you make another friend.