Quarters or no quarters

So now that the Capt has gotten beyond 2 and a half, we have been trying to explain he is going to be 3. We first told him he wasn't 2 and half anymore, he was 2 and 3 quarters. He was very upset and put out his hands and said "but I don't have any quarters!" "I'm 2 and a half!" Now I've been prompting him to tell people he's going to be 3. Unfortunately he is one of the younger kids at school and now he tells people, "I'm gonna be FIVE!" With the appropriate hand gesture. Sometimes he laughs so I'm thinking he might be doing it as a joke. Hmmm....