You know what would be interesting…

…if an oven had TWO knobs – each marked 0 to 350 degrees. With an additive effect. Therefore, if you wanted to bake at 450, any combination that added up to 450 would work (one knob at 350 and one at 100, for example). Not only would this help teach addition, but also degrees of a circle, at the same time. You’d have to have a separate one for choosing bake or broil, though.