This was a challenging board for my child, but still small enough for her to stay with it. Great to practice concentration and patience. We had to put it to the side a few times, but very rewarding for her when she was finally able to do it. Can even be used through to 5 years old to create a game/challenge of where child beats their own best score on how fast they can sort. Quality is great and allows for many years of use and still be able to pass on to another child to enjoy.