Making rice krispy treats with your kids is one of the funnest things you can do and you have something that taste great too. Melt a stick of butter and slowly melt in a bag of marshmallows. Once the marshmallows are melted stir in your rice crispies, about a box. If you add peanut butter in with the melted marshmallow before you stir in the rice crispies that really yummy. Pour mixture into a 9 X 13 pan and refridgerate until firm. Then cut into squares.