The Xbox console has several family features that can help you limit the types of games that your children play, the types of content they are able to access, add screen time limits, turn off chat, and adjust purchasing options. You can choose to adjust Parental Controls through the Xbox itself, or on Xbox Live through your computer.
To access Xbox parental controls:
Set parental controls on your Xbox 360 console
On your console, go to Settings, and then select Family.
Select the gamertag of the child whose settings you want to adjust.
Under Privacy & Online Settings, select Change Settings.Update the settings and then exit the screen to save.
Set parental controls through your computer
Sign in to your Xbox account.
Select My account.
Select Security, family & forums.
Select Xbox 360 Online Safety, and then select the account you want to adjust. (Your child’s avatar will be shown here next to your own.)
Select Allowed or Blocked next to the areas you want to limit or allow access to, and then tap or click Save.
For more information and guidance, take a look at the Parental Support page on Microsoft's website or Common Sense Media Xbox page.