Channel 4 news reader Jon Snow and architect Lord Rogers are among supporters of the independent Moat School, which is to be converted from a former comprehensive in Fulham, West London. Other patrons from the world of showbusiness and films, most of whom have personal experience of the condition, include Brian Conley, Ronnie Corbett, Susan Hampshire, Jeremy Irons and Anthea Turner. Chelsea footballer Dennis Wise is also a supporter.
Experts are divided over the causes of dyslexia, which causes children to mix up letters and have difficulty with reading.
Broadcaster Jon Snow has a daughter who is dyslexic.He believes state schools are failing such children at present, with little money spent on their special needs. "People are trying to set this school up because they are absolutely desperate," he said. "It would really set this government's commitment to education apart if they got down to addressing this issue, but it will take enormous resources."
Lord Rogers said: "I am dyslexic and some of my children have dyslexia. There is a horrific poverty in the education system for children with dyslexia. When I heard about the Moat School I really wanted to help.It is unfortunate that it is a private school, but it is better than nothing. Dyslexia is a condition that can be turned to an advantage if a person is given the right education. I found a way of expressing myself by chance."
Ronda Fogel, who is a founder member of the Moat School, trustees is campaigning to raise money for the school, which will initially take 30 children.
Her own daughter is severely dyslexic. She was faced with the hard choice of leaving her daughter to fail in the state system or sending her to an expensive specialist boarding school. The Moat, a day school which will only take on children aged 11 to 13, will not be ready in time for Ms Fogel's daughter. She is 14 and is currently attending a specialist unit at a boarding school and will start her GCSE courses this autumn.
Ms Fogel said: "My daughter goes to a fee-paying specialist school. I didn't think we could afford it at first. But there was no question that was what we had to do if my daughter was going to get anywhere in life.
"She could have stayed in her mainstream school with some dyslexic help, but that was like papering over the cracks. Going to the specialist school was a turning point. Now she is succeeding and has bags of confidence."
Organisers hope local education authorities may send dyslexic children to the school.Sponsored bursaries may be available for children whose families are unable to afford the fees of about pounds 12,000 a year.
Work is ready to begin on the first teaching block, planned for opening in September, but it could be delayed if the money is not raised in time.
The Constable Trust, set up to raise money for school, has so far raised pounds 700,000. Another pounds 250,000 is pledged if the trust can match that amount from other sources. So far it is pounds 210,000 short of that target. If it is reached it will bring the total to pounds 1.2m - enough to open the school in September. A further pounds 500,000 will eventually be needed to realise plans for the next two phases.
The site of the former St Mark's Church of England comprehensive, next to Fulham Palace Gardens, is being leased from the London Dioceseboard.
The school plans to offer a full range of specialist support for children along with space in the curriculum for the kind of subjects that dyslexic children often excel in, such as art, drama and architecture.
The Department for Education said it would be one of only a handful of specialist schools for dyslexics across the country.
n The Constable Trust can be contacted at 0181 458 2064.