hi i am actually doing on right now, we have brought canvas's and painted them then put the kids hand prints onto them the canvas's cost us $2.25 each and we are selling them for $20 bit of glitter and stickons and they look awesome.
Something different and not too hard also a garage sale works well too, hire out a hall and get the parents to bring stuff then sell it!! Easy, long weekends work well, we did this over easter holidays and raised $4000.
hope this helps.

kim