I use this site with my students. It tests if a web site is accessible in China. I have each of my students test ten commonly used web sites. Sometimes I just tell them to test the first ten web sites that they use that evening or in classes that day. The next day we first discuss the results in a general fashion, and then we compile our data from the class as a whole to get some more general statistics, which always leads to more insights and conversations. Both the first and second nights, they write a paragraph response to their experience. I think this sort of activity would work well with students of all ages. As long as they can copy and paste, they can test web sites.
An extension for older students would be to dig under the surface of the testing web site to determine the agenda of the creators of Great Firewall of China and then look in more detail at methods and targets of censorship in China and also in their own country, community, and school.
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