This puzzle involves moving balls within it to create a center of gravity and achieve balance. It helps develop observation skills, reasoning skills, problem-solving abilities, and lays the foundation for scientific thinking. This is a toy from Kodomo Challenge Hopp for 3-4 year olds, but children aged 6-7 can also enjoy it. I found and printed the example images from the internet. There are some scratches from use, but it's still perfectly playable. One orange, one green, and one light green ball are missing. Popular keyword: Kodomo Challenge