Asking a guy i dont really even know to prom?

So there is this guy In 2 of my cles. We dont talk at all unless we are working in groups and we HAVE to. I find him as a sweet and quiet guy. dont know if he's going to prom. and no offense he's not that attractive so i dont think any girl has asked him, or him asked a girl. ANYWAY i want to ask him. :) but would it be too awkard? prom is coming up FAST in like 4 weeks. and i need a date quick. my other two choices for prom started to act dumb and iffy (nother story lol) but so....what should i do? how should i ask him? should i even ask him? thanks i apreciate you all reading this :)