Another Pinner said: "This kept my 2 year busy for an entire hour and my 4 year old busy for 2 hours! YAY! Drop vinegar tinted with food coloring onto a pan filled with baking soda. Sheer minutes of colorful fizziness!!... Pretty sure we will be doing this soon!
Cool the kids off with a homemade sprinkler. Take a 2 liter soda bottle, poke holes in it. Attach to a garden hose via a male to male adapter that cost less than $5 at Lowes. Toss over a tree branch and let hang. You can adjust how the water sprinkles by adjusting the water flow. When the bottle gets beat up, just replace it, no additional cost!
Combine the following in a little bowl: 1 tablespoon self-raising flour a few little drops of food colouring 1 tablespoon salt Then add some water to make a nice smooth paste. Paint away on a nice thick sheet of cardboard (if you don't have enough paint brushes use cotton buds - they work really well). Microwave the design on high for 10 - 30 seconds until the paint puffs and it's all nice and dry.