Questions system for a classroom

Ok, so i recently had an idea for a project. The idea is to have a small Arduino system that would have a touch toggle sensor, (http://www.adafruit.com/products/1375) that would send a signal to a main Arduino that would have LED's to indicate that that student would have a question. Now, i would need there to be 30 students. I have a an idea of what i want it to do, but not much of an idea of how to do it. My idea was to have it send over bluetooth, although not entirely sure how long that signal can go http://www.adafruit.com/products/1327. Although i could probably use wifi if it comes to it. The main system would be up near the teacher's desk/computer, so the signal would have to be around 75 feet. Also, I can't figure out what arduino to use for the student and the teacher systems, because of the need for the dongle, and 30 LED's

So, would this be able to be done, and if so how much work would it take, since it seems simple.

Also, a part list would be great

Seeing that a bluetooth device can only handle 7 simultaneous connections, how do you propose to handle 30?

Well then I'll use Wifi

Henry_Best:
Seeing that a bluetooth device can only handle 7 simultaneous connections, how do you propose to handle 30?

7 into one
that one records those seven. plus that relay server, so it sends out one byte.
seven of those servers is 49 remotes, 7 relay servers into one master.
56 people in the class ?

each

dave-in-nj:

Henry_Best: Seeing that a bluetooth device can only handle 7 simultaneous connections, how do you propose to handle 30?

7 into one that one records those seven. plus that relay server, so it sends out one byte. seven of those servers is 49 remotes, 7 relay servers into one master. 56 people in the class ?

each

Now calculate the cost...