Teachers in specialist schools who do not teach the specialist subject feel resentful and marginalised, a new study has revealed.
Researchers from Birmingham university who spent three years studying a performing arts college found the disadvantages of specialist status outweighed benefits.
In their report on Queensbridge and Fox Hollies school, presented at the European Conference on Educational Research in Crete, they say that the change set teacher against teacher.
"Staff were concerned about the whole-school commitment to an arts identity, which would invariably impact on their own subject. There was a feeling of being distanced from developments."
Arts staff were also ambivalent. One mentioned resentment from other teachers, when pupils were forced to miss lessons to take part in performing-arts projects: "We have almost become a peg for people to hang their frustrations on."
Arts teachers were expected to act as consultants and advisers to other schools, but received little training for these roles.
The report says: "Wider reputations, and new money and incentives I brought more demands to the same, heavily-overworked staff."
Researchers did, however, find the new status increased pupils' self-esteem and confidence.
Tim Boyes, Queensbridge head, said: "Specialist status has meant that people are asked to do too much, and they have got worn out. You need to focus on whole-school improvement, so all the goodies don't go in one direction."
Queensbridge and Fox Hollies was the first Birmingham school to receive performing-arts status, when its bid was accepted in 2000. The school's popularity increased with 195 11-year-olds requesting it as their first choice in 2002, compared with 136 in 1999.
A 2004 inspection found that teaching was satisfactory, but that the quality of the curriculum overall was unsatisfactory.
Barry Benn, co-author of the report, said: "People don't like it when something is thrust on them, so their natural response is to be negative."
The Specialist Schools Trust spokesman said: "Specialist status brings a huge number of benefits to schools. That is clear both from anecdotal evidence and from academic results."
The Effects of Specialist Performing-Arts College Status on One Case Study School, by Tansin Benn, Barry Benn and Brigitte Doyle, is available from: email@example.com