How are schools handling requests for web 2.0 apps?

I have been asked to do some research and find out how schools are handling teacher requests for access for web 2.0 apps.  Since there are so many and new ones are created daily what steps/policies/forms/requests are districts requiring before teachers implement an app with students?  Does anyone have any such policies for each level (elementary, middle, high) they could share? I need information for a February 18th meeting.

Thanks!