Hundreds of parents and children are desperately scrambling for secondary school places after Turing House School was refused permission to open in September.
Uncertainty over a permanent site for the free school meant the minister for schools and Department for Education (DfE) deferred the opening until September next year, despite giving it the thumbs up last spring.
Parents were assured the school would open in temporary accommodation in September before a permanent site was secured, but the reverse has left 150 children without a guaranteed school place.
Parent Paula Muncey, 47, whose 10-year-old son was due to start at the school, said the situation was absolutely scandalous.
She said: “Everyone is shocked, angry, tearful, devastated and thinking ‘what are we going to do next?’ We had no reason to think it was not going to happen and it feels like the rug has been pulled from under us.
“I now have to send my son to a school that I have little faith in.”
The announcement on Wednesday, March 12, came just nine days after offers were made and parents have until March 17 to decide on another school.
Mrs Muncey, from Teddington, said: “There is a real trust issue now and parents may not want to risk putting their name down for a free school.
“I am sure there are some parents who will have rejected their other place and some children are not going to have a place even at their second choice.”
The original school proposal was put forward by a group of parents and charity the Russell Education Trust (RET).
Senior adviser at the RET Richard Elms said the school was incredibly disappointed.
He said: “Unfortunately the minister feels that things have not progressed enough in terms of a site and has deferred the opening of the school.
“Everyone at the school is extremely disappointed. But that pales into insignificance the disappointment of the parents.”
In 2012 it was decided various sites the school was interested in were unsuitable, including the National Physical Laboratory in Teddington and Clifden Road in Twickenham.
Councillor Stephen Knight, leader of the opposition in Richmond, said the debacle raised questions over free schools.
He said: “The whole process of starting free schools is clearly seriously flawed. It was always a bizarre fantasy to be offering places for a non-existent school.
“Even if a site had been secured by now, it realistically takes four to five years to plan and build a new secondary school and the idea that you can provide all the facilities in the meantime in Portakabins or converted offices is simply unrealistic.”
Richmond Council said all families who applied to the council have received another secondary school place.
But one parent said her daughter was left with her fourth choice of school, forcing her to get two buses to get there each day.
A council spokesman said: “We recognise that for the many families that backed the school, this will be a disappointment. The council is very keen to offer whatever help it can to assist the school, so it can open in 2015.”
Parents have set up a meeting with Twickenham MP Vince Cable on Friday, March 14.