1) Check your local bowling alley. Mine has $1 games from 9-4 on Fridays.
2) Blow bubbles. Use different things as wands for fun (spatula, large bubble wand, metal hanger bent into a shape, etc)
3) Hang a sheet on the clothesline and let the kids go to town making a masterpiece. Use washable paint and you can hose it off and start again.
4) Make bean bags. Grab some felt (25 cents each), a few bags of beans or some dried corn (few bucks) and some tacky glue. Cut felt to desired size, glue 3 sides and press with heavy books until dried. Add beans. pin all the beans to the closed side of the beanbag and glue the last open side. press with book to dry. use any container (box, pot, etc) or even draw a target on the sidewalk with chalk. I did this yesterday and only had time to make two beanbags, but my son had a riot with them..
5) Have a picnic - inside or out. Make a snack for dessert (cookies, rice krispy treats, ants on a log), sandwiches, finger foods.
6) Grab a package of chunky plastic fish from the $1 store and some magnets. Super glue a piece of magnet onto each fish. Tie a string to a stick and attach a magnet to bottom. Let the kids go fishing in the bathtub. (Even cooler? if you have those color bath tabs, put green in so they're fishing in a pond!)
7) Here is a site with a TON of games and activities.
FAMILY FUN