Should I oval it?

I am accustomed to my kids taking things literally, but I've come across an instruction that is REALLY starting to annoy me. In one of our son's books, rather than writing out the instruction "circle it" it gives the instruction with a picture of an oval + "it". The first time my son read it he said, "so I oval it?" Good question. Why not be accurate and print a circle + "it". Well, the problem is that you often can't "circle" some things, you really do have to "oval" them, but we don't say "oval it" we say "circle it".

I can say that in the first three and a half decades of my life, I never noticed the difference, or had a problem "circling" something in the shape of an oval, but now every time I ask my son to "circle" something, I find my self wanting to say "well, you may have to oval it."