Disruption and even violence is an increasingly common feature of college life, according to new research due to be published later this year.
Problems range from verbal abuse to fights, drug use, car park road rage, and even wheelchair ramming among increasingly fraught students with special needs, according to evidence collected by the Further Education Development Agency (FEDA).
Researchers say problems tend to be swept under the carpet by some colleges which are anxious to maintain their reputation in the increasingly competitive market for students.
They are producing new guidelines to help senior managers to nip problems in the bud, and a legal manual giving instructions on everything from physically removing a violent student to the proper way to handle an expulsion.
Many groups do not acknowledge problem behaviour as a factor in colleges, arguing that further education is voluntary and therefore disaffected students will simply stay away.
Neither the Association of Colleges nor the lecturers' union, NATFHE, rates student behaviour as a major cause for concern.
A NATFHE spokeswoman said: "It has come up sporadically over the years, although not on the kind of scale which appears to be developing in schools.
"Obviously there are differences because FE is not statutory, and there are older students who elect to be there."
But she did acknowledge that there had been problems, particularly in inner-city campuses, involving security, drugs, or rival groups of students.
AOC policy director John Brennan also pointed to some isolated incidents in colleges, but said there was little indication that colleges faced major problems.
FEDA researcher Carol Mitchell said she had encountered much anecdotal evidence of disruption in colleges, and a real demand for help from teaching staff.
She said: "We called a seminar and invited various interested parties to contribute evidence and found evidence of a whole range of challenging behaviour or disruption presenting in the sector.
"There are issues here for all colleges whether or not they like to admit it.
"Colleges are very concerned about their image, but in order to improve their image they need to be addressing this.
"We have been looking at any kind of behaviour which causes some upset. It could be improper language or verbal abuse, bad behaviour in car parks, drug dealers coming into college, or disruption in classrooms. There could be students in learning resource centres who are not focusing on their work.
"There have also been reports of fights and violence, although those are much more rare than the sort of everyday behaviour which might cause offence.
"In one college, there were problems with wheelchair ram-raiding. "
Eight colleges are currently working on projects to deal with potential problems. Their reports will form case studies of good practice, due to be published in November.
The work includes:
* Disruption in libraries and other open study areas (City and Islington College);
* Common-room problems (Bury College);
* Problems involving students with learning difficulties (Exeter College);
l Developing skills for students with disabilities (The National Star Centre in Gloucestershire);
* Policies for use in large colleges (Bradford and Ilkley College);
* Ethnic minority tensions (Luton Sixth Form College).
Mrs Mitchell said: "Just as FE staff have to be aware of health and safety issues so they also have a duty to be aware of these issues of disruption.
"The sector has changes and it is attracting a wide range of groups. We are getting more disaffected pupils and some colleges are taking in 14 to 16-year-olds who have been disenfranchised from the secondary sector. What we are advocating is a whole college approach. If there are clear policies and codes of behaviour are set out then there should not be such great problems."