Encourage your kids to talk to you without fear of punishment about what they read and see on the Internet. Place the computer in a common room, not a child's bedroom.
Children of any age need their parents to establish clear guidelines about Internet use. Establish a set of rules that you and your child can agree on. Then post the rules above the computer or in another common space.
Teach your children not to share personal information in e-mail messages, chat rooms, message boards, blogs, social networking sites, or other places online.