To prevent inappropriate online interactions, here are some good family guidelines to follow...
Talk about the importance of making smart decisions. Establish rules about online activities and post them by the computer.
Place computers in common, open areas.
Consider using parental controls, blocks or filters, but realize that nothing takes the place of parental supervision.
Limit kids' instant messaging (IM) use to friends you know. Your child should be able to put a face to every name on his or her IM "buddy list."
Remind your children that people in chat rooms and on message boards are not always who they say they are. Kids should never agree to meet in person with someone they've "met" online. Nor should they give out personal information, such as their name, street address, school or email address. If your teenagers maintain personal websites, make sure they don't post such information or share photos of themselves.