Have the computer in the Lounge and put on a pass word that only you know so they cannot go on when you are not there. If this a a little restrictive you could try one of the software packages that blocks access to certain sites such as cyberpatrol.
Alienware 17 R4 2017 review
These brilliant Lego posters show just what children's imaginations are capable of
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Comment réinitialiser votre PC, ordinateur portable ou tablette Windows ?