Disney can be crazy expensive when it comes to souvenirs. At the end of EVERY ride you exit into a themed shop. Your kids are excited from the great experience they just had and they want a ton of items of that character. The cheapest way to handle this is the coin smasher machine!
Be sure to bring tons of shiny pennies and quarters to the park(s) with you. The kids can hunt down the machine, put in the coins (51 cents for a penny smash), and work the crank to print out their stamped souvenir! To store all your new treasures, be sure to purchase a booklet made to hold them. You can find them in most stores in the parks and at Downtown Disney.
Happy Stamping!
