Speaking from the airline perspective, we have attempted to assist groups with this before but the hassle factor was simply not worth it. The teams failed to carry the correct entry documentation for the destination country (you do need a passport to fly internationally), showed up late (hitching a ride to the airport doesnt guarantee you get there in time for your flight) and were highly unprofessional and frustrating to deal with (changing of names at last minute, asking if we could reschedule our flight, drop them off at another destination, etc...). As a result, we have taken a decision NOT to deal with this kind of student group sponsorship anymore.

You will find most airlines operating from the UK have had similar experiences and similar policies unfortunately.