Peter2 said: "It's great to write a composer! I know somebody that did that once as a teenager and actually did get a letter back. But I suppose he could well have more letters than he can handle, so it's possible you could get a form response saying he's too busy. No reason not to try, though.
You don't say what level class this is--high school, college?--and that might make a difference deciding what to ask. I would suggest that before you write you see what topics he has already addressed. There is a huge amount of material out there--interviews on YouTube, articles in magazines, and also many good books about Sondheim, at least in part (the most famous of which is probably Horowitz's "Sondheim on Music"
. Above all, take a look at his great "Finishing the Hat" two-volume set, if you haven't already--his extensive commentaries throughout it are incredibly enlightening and interesting.
Good luck!
Hey Peter 2, it’s a college class. The class actually focuses on Sondheim’s lyrics and we’re actually using Finishing the Hat and Look I Made A Hat as our textbooks, so from that research we’re supposed to think of questions to ask.