Windows 7 has a very effective tool called parental control which can help you to monitor and filter web sites your child visit, time they spend on the computer, software and video games they use, etc… Comprehensive and effective tool, but again fairly simple to implement, as you will see in this tutorial. One constraint however, you must have an account with administrative rights on your computer which will be protected by a password (to prevent one of your children does not change the protection settings). Also, to enable web filtering, you also must have a Windows Live (Messenger, Hotmail, etc…) which will be associated with your web filtering settings.