Nice puffballs.....Now find yourself some oak trees and you'll find some real mushrooms. Some people like puffballs however I don't. You must make sure with puffballs that there are no color changes inside the puffball or that there are no gills beginning to form on the inside of the mushroom. These are signs that it oculd be one of the poisonous puffballs, or the puffball is getting old, or that it's an amanita.
if you really want to learn mushrooms find a club in your area on the american mushroom society website that will teach you all that you need to know.