For my daughter's third birthday we had an M&M party, her favorite treat.  It was a very fun and colorful party because you can do so many things with M&M's.  For decorations I found mylar M&M balloons on ebay (you can also find them at Kroger,but they're much more expensive). I weighted them down with individual bags of M&M's and these, along with some M&M rings, became the party favors for all the guests.  I used lime green, yellow and red paper plates and stamped a white M on primary colored napkins. Instead of making a large cake, I made cupcakes and frosted them all with primary colors.  I put a white M on the top of each cupcake and then arranged them on a tray that had M&M's scattered on it.  It was very cheery and colorful.  The games we played were non-competitive since we had children ranging in age from 2-10. Our first game was similar to "Fruit Basket".  I collected M&M boxes from the grocery store (the large cardboard ones that hold the large bags of M&M's). I cut out the M&M circle and made sure I had pairs of each color.  The children stood in a circle and were given a cardboard M&M. When their color was called, the children had to run across the circle to trade places with someone of the same color M&M while trying to avoid getting hit with a pillow. The other game we played was with a 6-colored parachute and matching bean bags that were made to look like M&M's. The children chose a color on the parachute and the colored bean bags were placed in the center.  The object of the game was to keep your colored bean bag on the parachute while trying to bounce the others off.