multiple WNDAP360 in one room, 100+ devices

Hello everyone, we have a WC7520 controller with about 34 WNDAP360 to cover our entire secondary school campus. Its working quite well. But some of our spaces are starting to assemble 90+ students in one area, each student can have one or even up to 3 devices. Obiously that one access point in the room is a bit overworked. :) I was informed that one WNDAP360 device is good for about 40 onnections. What are my solutions to connect 90+ devices in the same space? 

1. If I put 4 WNDAP360 Wireless Access Points in one room with 90+ connections, will the access points automatically load balance the 90 devices? Can I even put more than one WAP in a room? Do I need to configure their radio frequency or are those days gone? 
   
   
2. On a different scenario, lets say there are 4 access points in the room, but everyone is crowded around ONE access point. Wil lthe other remaining access points attempt to balance the load? Will their devices automatically connect to the strongest signal? Is it their personal device that "decides" which access point to connect to or is that the "decision" of the access point? What if the other access points are a good distance away from the one that 90 devices are trying to connect it? 
   
   
3. Unrelated question … can I add a MAC address to the WC7520 controller? Anytime it sees a NIC with that MAC address, it’ll provide internet access. This will save me from having to enter the password in the machine every time I change it. I’d also like the ability to upload a list of MAC addresses that I authorize to access the internet. Is this possible?
   
   
4. What is the best way to allow great interet access for 50, 100, 150 devices in the same room? 

Thanks!