You need to work closely alongside some teachers. The teaching profession is busy and often labyrinthine, with its own unique bureaucracy (and camaraderie). And as for expecting a teacher to plunge in and start using a web app, you must first find out if they can effectively use a computer...

If you're in the UK, be sure to check out the Times Educational Supplement website, in particular the forums: http://www.tes.co.uk/forums.aspx?navcode=14

There's also the BETT show every January, essential to check out the other players you're up against: http://www.bettshow.com