What is a nice, cheap thank you gift?

Two of my classmates have been taking notes for me this week as I’ve been unable to attend class. We barely know each other, they certainly didn’t need to help me, they just offered knowing how hard of a time I’m going through. I’d like to do something nice, not to repay them, but just to say thank you.

So what should I do? Anything that would require a bit of time is fine, I’d appreciate the distraction.