There not too bad, but adults end up doing a lot of the work. This year we're looking at doing a "free car wash". Really it boils down to being a car-wash-a-thon where you get businesses to sponsor car washes and pay out $X per car wash (any amount is fine) and in return you can include them on a sheet of paper that is given to each car washed as a sponsor. The paper can lists them as a sponsor and encourages those who got their car washed to patronize their businesses. Businesses can even provide you with coupons to put on the paper if they want.