Does it mean anything when....?

Does it mean anything when a guy smiles at you when you dance with him? I don't know much about guys, seeing as I have never dated or have been asked out. At my high school, we were learning different dances like the cha cha and the waltz. Everyone seemed uncomfortable dancing with each other. We had to rotate partners every few minutes. I didn't know many of the guys who I danced with, some were younger and some were in higher grades. A few guys smiled at me while I danced with them, including a guy that I used to like. (He has been staring at me a lot ever since we danced) Were they just having fun or could it mean something more?