The Slider?

Waaaaaay back in October, when we started addition, I thought of making this..... thing.  It was sort of like a rekenrek, but adaptable.  This is what I came up with!  What makes it so awesome is that it can be changed very quickly for whatever numbers you need because it's just clothespins.  When you are trying to find all the ways to make 10, just put 10 clothespins and slide them from one side to the other to make sets.  To subtract, the clothespins match your first number, then slide away one group.  This is not only great for "take-away" subtracting, but "how many did we take away" or "how many did we start with" subtraction!  I made this slider? with 2 of those really strong white magnets with hooks on the front.  I cut the bottom section off a wire coat hanger (it has to be something rigid) and hot glued it in the two hooks.  Then I glued monkeys on the fronts and colored the clothespins yellow with a Sharpie to make "bananas." EASY!