Seven out of ten state school teachers would be unhappy working in a new "free school" set up and run by parents, a survey has found.
But independent school teachers taking part in the research were more positive about the schools: only half said they wouldn't want to teach in a parent-led free school and a quarter said they would even be happy working in one.
Teachers taking part in the study complained that parents do not have the time to devote to running a school, and those who did had selfish motivations.
Danny Williams, a head of department in a Telford and Wrekin secondary, said: "There is enough trouble recruiting parents to engage with schools as it is - in many cases it will be a 'hobby' where the novelty will quickly wear off, causing long-term problems."
One primary teacher who used to teach in a Spanish school run by parents added: "They were doing it to court favour and (get) positive exam results for their children."
Most staff - about 85 per cent - also expressed concerns about the impact of academies and free schools on their pay, conditions and pensions.
The scepticism over free schools also stretched to academies in the survey of 1,856 members of the Association of Teachers and Lecturers.
About 40 per cent of state school staff said achieving academy status would be detrimental to their school, while a quarter thought it would have no impact. Nearly half said the academies programme was also unlikely to boost achievement.
Teachers also voiced concerns that the expansion of the academies could create a two-tier system. They were also worried about the involvement of private companies in education.
ATL general secretary Mary Bousted said: "Staff in state and private schools are rightly totally unconvinced that academies or free schools will improve education, and they are tired of change for the sake of change in education."
"The message coming over loud and clear from ATL members is stop meddling, treat all schools equally and give them all the support they need to get on with the job of teaching."