Discovering the gyro principle, this toy is very attractive. It works great but its handling requires care: it must tightly wrap the string and pull it takes a little tilt to prevent it from tangling on the axis. So a little difficult for a child of 9 years, but with a little practice (and advice) it is doable! This is a toy that many arouses scientific curiosity of children. Warning: it is a little heavier and with metal end caps so the station tile!