... some sport team travel at a local university ... want the bus to be WIFI equipped so the students can study while traveling.
a system that won't break the bank ...
Sorry, but no, there is no such system that will not "break the bank." The hardware itself is not expensive; I would figure less than a thousand bucks for the router, antennas, cabling, and installation. However you should figure to spend several hundred per month on the service.
You can "roll your own" or buy the system from Autonet that is mentioned in the article linked by pipes. The Autonet system has the advantage of one-stop support.
Simple.. If you have an air card, a wireless air card router will be the most cost effective way to supply your customers with on the road wireless.
Well, it's not actually that simple for Bryce's application. For one thing, a simple wireless aircard comes with a contract that explicitly prohibits using it for this kind of application. Same goes for "MiFi," Overdrive, and similar solutions, which are essentially what the Cradlepoint is but with the aircard built in.
In practice the hardware will be very similar. Autonet's system is little more than a more robust and higher-end version of Cradlepoint's unit. However the service contract will be very different, and Bryce will likely need more than one cellular modem active at a time.
A Cradlepoint, MiFi, OverDrive, or what have you will support perhaps 5-7 users "comfortably." More than that, maybe, if they are just doing Facebook on their iPods. But even two or three users with laptops downloading videos will bring a single 3G device to its knees, and you know if these kids are not paying for the service themselves and have no restrictions that's exactly what they are going to do.
Lastly, even if Bryce could somehow squeak in on a personal or family contract (as opposed to the commercial multi-user one he needs) and make it all work on a single 3G modem, the monthly usage is limited to 5GB. A busload of college kids can use that amount of bandwidth in a matter of a few days. after 5GB you are charged by the MB -- the second 5GB ends up costing $200, whereas the first only cost $60. Depending on how many days per month he would be operating this service his bill could easily rise to well over $500, and that's if he stays in "home" coverage. If he roams at all onto another network it can be an order of magnitude higher, and the news is rife with reports of people getting surprised by multi-thousand dollar data bills. Note that on a moving coach, it is almost a certainty that the service will be roaming some of the time.
Your solution probably works well for you precisely because you use it only to support one or two people and you are within the terms and limits of a personal plan. That's not the situation Bryce is facing. He needs a commercial account, higher-bandwidth hardware, and some kind of access and usage control system to ensure that his customers don't drive him into overage charges and that random folks who happen to be near the bus when its parked can't pirate his service.