I've been showing my oldest one change since he was 4, he's 5 now. I'm trying to teach him the difference between quarters, dimes, nickles and pennies. He gets them confused except the penny which I assume is because it's a different color. When did you start teaching your kids?
I don't know that we really started "teaching" our daughter about the differnt types of money. It was just part of her getting "allowance" and having to save parts of it for different things. She is 6 now and they taught about money in Kindergarten and just finished a money section in math in 1st grade.