Here is a great recipe to make with kids or grandchildren because it is so easy:
Kids Favorite Cookie Bars
melt 1 stick butter and pour in bottom of 13 x 9 pan.
Crush 1 1/2 pkgs of graham crackers (this is 1/2 a box of grahams)
Mix into the butter and pat down to make flat crust.
Pour one regular size pkg of semi sweet choc chips over that.
Pour one regular size pkg of peanut butter flavor chips over that.
Pour one small can sweetened condensed milk over that.
You can add nuts and shredded coconut to these layers (under the sweetened milk) before baking at 325 for about 15 minutes, or until you can no longer see the milk. Edges will be a little bubbly. Cool completely and cut into bars.
I'm sure you can come up with hundreds of variations to this. Butterscotch or White Chocolate chips, M&Ms, etc.