Money talk

I've been trying, lately, to teach Jack what money is. So far I've been completely unsuccessful. Here's a recent conversation we had.

Jack (holding a dime): "Look Mommy! A pretend candy!"

Me: "Jack that isn't candy, it's money."

Jack: "Be so nummy!" (nummy means yummy in Jack-speak)

So far, all he understands is that sometimes I carry these round metal things in my purse, and I like to pretend that they are delicious.