Games are the fun way for children/teens to learn interactivity. For adults it just fun. However the younger a user is introduced the younger they can adapt to the technological age we now live in.
Digital games like any other games throughout history teach core skill sets like patience, strategy, organizational skills, and reward through practice. Hand/eye coordination and focusing have also been proven to improve from playing games. Not to mention giving them access to grown scenarios they might not have opportunity to witness till life throws it at them, and we all know how nice life can be.
If you are interested in introducing user experience early go to Early Integration
These games were proven to be successful within those ages. The children could handle the interactivity and the concept of the games. These catergories will increase as the test subjects get older:)