We are looking at deploying iPads. We have just brought our first one and have been experimenting this week.
We use HAP for remote access and so far, using HAP seems to work reasonably well on an iPad. You can download or open in a new tab most common file formats. You can upload photo or video straight to the Staff Public drive - you don't seem to be able to rename from the Camera Roll or from HAP once uploaded which is annoying but in general, this could be a decent way of accessing the school network.
What I like the most is we simply added the server IP that HAP is installed on to our Ruckus wireless ACL which means this can be accessed via the guest WLAN. The only devices they can access is the Smoothwall box and the HAP server - which solely runs HAP.