My daughter has used these at school and was delighted when I discovered them and bought some for her. They are such fun! And they're reusable! We use them to practice spelling words, make fun designs, write messages, etc. This big box is the most cost-effective way I've found of purchasing them.I've packaged up sets of about 50 into ziploc bags to take with us when we go on a long trip. They'll be great for projects on the airplane tray tables! And car windows when we drive long distances... They do leave some residue sometimes, but I've found it easy to clean up. They're small and yet provide many ways to play, which is a must for travel toys in my book... My only question... Do they handle hot temperatures?? We'll see.