it sounds like they've got discretion over whether to pay you extra or not. i haven't heard of anyone working camp outside regular hours, but if it's only a three hour per day camp and you have a good relationship with your school, i wouldn't ask. do you get to go in late, or will you be desk warming starting at 8:30/9? if you don't have to go in until like 2 or whatever, i definitely wouldn't ask. if you have to desk sit and your total hours per day will go beyond what you're scheduled to do, maybe consider asking. i have a good relationship with my school, so when they ask me for things occasionally that are less than convenient for me, i try and do them. i look at it as a give and take for all the random class cancellations i get sometimes. if you're really curious what the protocol is consider asking your coordinator or someone who would know what usually happens in this kind of situation. :)