You could let them make a site about pokemon, drgonball z, whatever they like. Let them search the inet for images and stuff. Then let them put it together with some links to related sites.
This way the'll look at other sites that they are interested to, might give them ideas for their own page. And with creating a page, they'll learn how they've got to put it together, and because its a subject they like, they spent more time on it. In turn they'll learn more.
I'm not a teacher or anything related so I could be COMPLETELY wrong, but it might work.
Anyways, use a topic that they like or they'll lose attention in 5 mins...