Honestly, what is this doing in a volvelle collection? It's round, I'll give it that. This is a game card from one of a series of bingo-style educational games produced by Milton Bradley. They had time-telling, arithmetic, phonetics -- that sort of thing.
This is 5.75 by 3.25 inches. I promise to give you a much better wheel tomorrow. In fact, it's the most expensive wheel we own. Stay tuned!