These are some excellent sites for parents and teachers interested in teaching their children how to keep themselves safe online.
The Hector's World Safety Button provides a safety strategy which children can use if something on-screen upsets or worries them. It is a free download and a small file. Your child can just click on Hector who then covers the screen with a soothing underwater scene and gives the child a positive message for clicking on the Hector Button, and encourages them to get adult help.
I highly recommend put this on all school and home computers, but remember children must be taught how to used it and when.
Hector's World™ presents animation that feature residents of the undersea community of Silicon Deep. Children watch the characters as they learn how to stay safe online.