Fisher-Price Doodle Pro is an excellent toy for children ages three and up. This is a magnetic board that children can write or draw on. It comes with its own pen that is tied to the board to make sure it does not get lost. Once they write on the Doodle Pro you just slide the lever over that's at the bottom and it erases the board.
I've seen the Fisher-Price Doodle Pro comes in a few different sizes. They vary in price depending on the brand you buy (other companies make these too) or the extras they come with such as some models have a carrying handle. Some of them also have a slide out drawer that holds plastic stamps that help the children make shapes on the board. I use one of the basic ones which run about 15 dollars.
These are excellent for the classroom or at home to keep children busy. They are great for travel to keep children occupied and to keep them from getting bored.
I have yet to see a child that did not like this toy.