Get a piece of plywood and have someone draw and then using a jig saw, cut out a couple of different "robbers". Have someone who is artsy paint the board up to look like a bunch of robbers and such. Make it funny looking. Have the mouths cut out, possibly with missing teeth and such. Also cut out holes near the robbers guns (if guns will be ok for the picture). Anyway, the point is that this can be made into a bean bag toss that fits the theme of your event and can be used as a fun station where prizes can be won.
I also wonder if you could purchase sheriff badges for the kids?
inflatables. they are always a hoot. ( I have suggested these on several posts this morning...no, I do not rent them or get a kick back!! LOL)
'Cake Walk'. Doesn't need to be food.
Find The Answers. Make a list of questions that the children need to explore the school to find the answers. What is Ms. Wackey's first name? What room number does the spanish class have? Put them all in a barrel and pull out a 'winner'.
Cotton Candy!!! Popcorn!!! Drinks!!! Fun to do and raises funds even with moderately priced items!!