I think it is a very creative idea. May not work as well for children who have difficulty keeping track of them. I got one for my granddaughter and her mother loves it but she has not used it yet.
My niece and nephew love their sweatshirts. Since he's too little for his yet his cousin has been having so much fun changing stickers on his sweatshirt!! I'm so pleased with my purchase!!
Love love love these hoodies. Quality is excellent. Bought one in every color and extra large so my granddaughter can have for a long time. Very pleased with product & customer service.