For an easy recipe that solidifies the concept of fractions for kids, check out this article from the Chicago Tribune. (The recipe, along with further exploration and more math recipes, can be found in Eat Your Math Homework: Recipes for Hungry Minds— Charlesbridge, 2011)
http://www.chicagotribune.com/features/food/sc-food-0729-kids-math-20110803,0,258572.story