A lot of great ideas already - we have just come from a party where there was many ages, here are some of the things they all enjoyed as well as some all time favorites from Church carnivals/game day. Some of these require that you let the parents know ahead of time that you will be doing MESSY things and to send them in appropriate clothing and not dress up party clothes.
1. Make musical shakers out of plastic water bottles by using a GLUE STICK (much less messy than traditional glue) and tissue paper that was pre-cut. Save the tissue paper from Christmas presents and gather up water bottles from work or ones that you have used and put beans or dry corn in the bottles for the "noise". If you don't have enough water bottles, you can also tape together 2 plastic cups and put the beans or corn inside.
2. Decorate cookies or make your own ice cream sunday - lots of topping - you can even make your own colored sugar if you want by adding food coloring to regular sugar.
3. I am sure that most craft stores are currently or will be soon having clearance on pre-cut wooden Christmas ornaments - easy to paint and decorate - they don't have to be "Christmas" ornaments - you can have stars, bells, etc. anytime of year.
4. bobbing for apples - fill a small baby pool with apples and have the kids bob and get the apples.
5. Treasure hunt - you can put up a maze with clues in your backyard and even start on a pirate ship (blue blanket on the ground and each of the kids get a cloth to tie around their head and some face paint for mustaches, etc.) With the blanket, you can have a set story about the pirates - the parents or older kids wave the blanket like the ocean.... then follow the clues, end with a sandbox (small pool filled with sand or shredded paper, etc. and they can dig for "treasure".
6. GO FISH - make a simple fishing pole by having a dow rod or a stick with a string and then put a paper clip on the end... have someone under a covered table put "prizes" or clues to where a prize is hidden in the house or yard in a paper bag or on a picture of a cut out fish....
Agreed that they dollar store or the Target savings spot is a great place to find prizes and favors!
I hope that you have a great time.
blessings,
Stacy