Here are 4 posts from about 18 months ago dealing with why schools cannot ignore Web 2.0.

Thanks to @wikisaber_pt for tweeting the link to one of the articles, which reminded me  of its existence!

Why schools cannot ignore Web 2.0: Social Factors 

Why Schools Cannot Ignore Web 2.0: Technical Factors

Why Schools Cannot Ignore Web 2.0: Economic Factors

Why Schools Cannot Ignore Web 2.0: Commercial Factors

By the way, for a fantastic free book containing 87 Web 2.0 projects, go to the Free Stuff page on this website. By last week, this had been downloaded 39,564 times since March 2010.