JCoSS has launched an appeal to fund a new building in order to offer 30 extra places a year.

The Ronson Foundation, one of the cross-communal school’s major supporters, has already pledged a quarter of the £4 million JCoSS needs to raise.

The East Barnet school has offered a bulge class in previous years — though not this September. It hopes to raise its year 7 intake permanently from 180 to 210 next autumn.

“We have a waiting list around the block,” said headteacher Patrick Moriarty. “We’ve gone a long way to making this happen. We won’t wait for the building to be finished before we take the extra students. As soon as we have raised the money, we will put in Portakabins.”