Below are two threads with hundreds of ideas on fund raising and sponsership. It will need to be a team effort with frequent meetings with fundraising the #1 topic to get all kids and parents involved. Most teams face this issue and it is an important part of team developement. I doubt that any one thing will get the money you need, it will take many efforts, a little at a time. Good luck.
http://www.chiefdelphi.com/forums/sh...ad.php?t=68051
http://www.chiefdelphi.com/forums/sh...ad.php?t=68044