I purposefully cut the girls' sandwiches in two different directions giving Rose a triangle half and a rectangle half. I forget about things like this with my number three child. We've talked about shapes before, but not frequently enough. I wondered if she knew them. I pointed to the rectangle, "What shape is this, Rosie?" "A door,"she replied. "Yep," I agreed, "and a door is a rectangle. Can you say that?" Then, pointing to the triangle, I ask, "and what shape is this?" "A roof." Touche.