Zhang Guo Liang learned to make yo-yos (空竹) from his family and is a third generation artist of the craft. At one point his grandfather supported his family by making yo-yos. He is one of 54 artists in his Beijing district.
It is great exercise, but playing with a yo-yo can also be a form of relaxation. The basic yo-yo is shaped like two disks connected by an axle and is spun by a string wound around its center and moved by pushing and pulling the string with two sticks.