Ok, I have a few due replies. :-)
Gustie - I think it's clear now that I was suggesting aggregating into a vlan pool, not a single vlan.
Gustie - You mention that supporting AppleTVs and projectors in the classrooms is a requirement. If that's the case, I would definitely NOT use mobile IP. Otherwise, you'll have a client leave building-1 and enter a classroom in building-2; since they'll retain their IP from building-1, they will not be able to communicate with the AppleTV without some bonjour proxying (like airgroup, aerohive, cisco, etc).
bosborne - re: wasted overhead with vlan pooling . . . trust me. :-) The problem is that clients are placed into vlans by a hash of their mac address - that's all. There's no built-in intelligence to know whether or not they'll receive an IP on that vlan. Thus, there's a probability that some vlans will fill up while others still have [plenty of] leases. This is the variance associated with vlan pooling. I've attached a screen shot of client dispersion across the different networks in one of our pools. The pool consists of 23 /23s, equating to almost 11,500 IP address leases. Yesterday, during one of the problem times, we had 9,970 clients with an address. That's only 87% utilization, or 1,530 addresses still available. In other words, we had about three /23s worth of addresses not even touched, yet we had clients not getting an address. This is the flaw of Aruba's vlan pool implementation. I'm currently working with them to improve it; we'll see if something comes to fruition.