Answer:
You can always start with a simple greeting, and by asking how their day was. Then you can move onwards from there and bring up the class assignment. Also try making a casual comment to grab their attention, that can be a great conversation starter.
Explanation:
If you know a little about them, or know someone who knows them, then you can use this to your advantage, because you two would have something in common. Also along these lines, find a middle ground between you two, like something you both can agree on and like doing, after all, you both may actually find something to bond over.
I may not be a relationship expert in any way, shape, or form, but I hope this helps you :)