A couple of links I thought useful when showing pupils aspects of web design.
A bit of the history of the BBC site, some aspects of the design process, they might get the idea of consistency, navigation etc out of it. There are certainly a lot of good pictures for the pupils to look at.
http://www.bbc.co.uk/blogs/bbcinternet/2010/02/a_new_global_visual_language_f.html
http://www.bbc.co.uk/blogs/internet/entries/d0db2334-830f-3418-9dbe-0c72e87c0a0e
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