Once you've been to camp as a new camper, you become a part of the Mathcamp alumni community. Alums don't have to do the Qualifying Quiz again to apply as returning students: they are automatically invited to come back as a camper as many summers as they are eligible. (See eligibility.)
The process for signing up to return as an alum starts in January. First, we'll ask alums whether they might be interested in cominng back as campers, and if so, they fill out a short interest form. That interest form just gets students on our radar for the summer.
This is also when alums and their families can apply for financial aid. Alumni are eligible for the same need-based financial aid as new campers, and financial aid packages are independent of previous years; we simply work with families to meet the demonstrated need each year.
The second step happens in the spring: we ask alums (the ones who filled out that short interest form) to give us a firm commitment (of the form "yes, I definitely want to claim a spot" or "maybe, but my plans are still up in the air – I'll join the waitlist" or "no, I've made other plans, you can give away my spot"). Then we do a headcount of "yes" responses to make sure that there's enough space for everybody (we reserve up to 55 places for alums; if we hit the limit, we have a waitlist system), and invite students to start registering.
Registration for alumni happens at the same time as registration for new campers, and the deadline is in May. (See dates and deadlines.)
Lots of students come two, three, four, or even five or six times as a camper! Returning alumni play a big role in establishing our camp culture and making Mathamp the magical place that it is.