iPads in the Classroom
How do classroom manage apps for a number of classroom iPads
iPad 2
I would use Apple Configurator.
For the classroom iPads, you can use Apple Configurator to install apps on all iPads using a single Apple ID. Free apps are easy to add to Configurator. For paid apps, you will need to enroll in Apple's Education VPP program http://www.apple.com/education/volume-purchase-program/ which will allow a single Apple ID to purchase multiple licenses of an app. And best of all, you can save 50% of the cost on most apps when buying 20 copies or more. So even if you only need 15 licenses of a paid app, its cheaper to purchase 20 through VPP and save 50%. Using Apple Configurator, I would "Supervise" the iPads and install the apps (and configuration profiles) to all iPads.
Apple Configurator Resources
PDF: http://www.apple.com/iphone/business/docs/iOS_Apple_Configurator_Mar12.pdf
Video: http://www.apple.com/education/resources/videos/#introduction-to-apple-configura tor
Help Pages: http://help.apple.com/configurator/mac/1.0/
Also check out this guide: http://images.apple.com/education/docs/IOS_5_Education_Deployment_Guide.pdf
Hope this answers your question!
~Joe