One of the dilemmas encountered with using iPads in classrooms is the desire to display the iPad without being hooked up to an LCD projector. A mobile device begs to be free and not tethered to a cable. While the Apple TV has great promise, many schools have yet to move in that direction due to concerns with securing the wifi connection and configuring a school full of Apple TVs. Our school’s IT department came up with this solution which seems to be a solid compromise and solution. AirServer is an inexpensive application that can be installed on any computer and it turns it into an Apple TV wannabe device capable of displaying any iPad on the same wifi network. There are other apps that can do this as well and some are outlined in this article. http://ioswikis.mycues.org/groups/ipadresources/wiki/1ad2e/Reflection_Aerodrom_or_Apple_TV.html
This tutorial will show you how to set it up and use it with your students. Passwords are important to remember as the biggest concern I would have is a student guessing your password and displaying their iPad while you are trying to have a different instructional display.
A nice thing about AirServer was we were able to buy 20 licenses at a volume discount so it was very budget friendly.