You can carry over monies to the following year. You do need to 'earmark' the money to stay within most, but not all, state 501c3 guidelines. It is hard to determine what you will make from year to year as many schools found out with the Sept. 11 attacks. Our fundraiser was finished before the attack because we run it so quickly after school begins. Most school fundraisers had severe problems because they begain around the same time as the attack. Our school did extremely well, but 2 miles away, one of our other elementary schools did poorly 3 weeks later.
Earmarking the money can be easily accomplished without alloting specific items. We reimburse our teachers $75 (and the Clubs, the nurse, etc.) and in order to do that, requires us to carry over $3500. We also allow for administrative costs (yearly budget for paper, stamps, etc.), and emergency funding (something was stolen over the summer, something broke, etc.). Instead of looking at just the 'start up' costs, we actually carry over a years worth of the funding (start up would be one case of paper-we budget for the 2 cases we know we will eventually use, even though we just buy the one at the time). This way, we have a few bucks for those things that always come up. You may have a multiple committment to something, like the 3 year, $10,000 committment we made to our computer lab. Any monies left over could be 'earmarked' for that, even though you will probably raise the promised funds during the year another way.
Don't you just love creative financing?