~ Melt the margarine in a large pan over low heat on the stovetop.
~ Add the marshmallows. Stir until melted.
~ Stir in the cereal.
~ Press the mixture into a 10x15 pan (a cookie sheet).
~ When the bars have cooled, let the children take turns selecting a cookie cutter and pressing it into the bars. Help them to remove their shape and to decorate it with sprinkles.