A grammar school has been forced to take on 50 more new pupils this year - a number of whom did not pass the 11 plus, it has emerged.

Ramsgate’s Chatham and Clarendon Grammar School normally offers 180 places to Year 7 children but this year enrolled an additional 50 - the equivalent of two more classes and the highest intake in the school’s history.

The school has been obliged to take on the extra pupils after a Kent County Council panel approved their appeals - many of whom had failed test.

The exact number of pupils admitted who did not pass the Kent Test is not known but the head of a group of neighbouring schools said the intake raised questions about whether schools were genuinely selective.

Paul Luxmoore, the executive head of the Coastal Academies Trust, said he was concerned about the impact on neighbouring schools of such a large expansion.

While it is not uncommon for schools to have to admit more children who have appealed, such a large number is rare.

Mr Luxmoore's trust runs five schools in east Kent - including Dane Court Grammar.

He said it had left other schools with fewer children than they had planned for - affecting budgets - and would make it more difficult to improve standards.

But Chatham and Clarendon Grammar School said it was left with no alternative but to accept the extra children as they had successfully appealed through an independent process.

Mr Luxmoore said: “This unplanned and very sudden expansion of their roll will be to the detriment of local non-selectives, each of which will have budgeted and staffed for the students they had been allocated.

“It is already the case that there are too many selective places in Thanet for the numbers of children passing the Kent Test.”

Schools in the area already struggled to meet government targets and ‘survive hostile Ofsted inspections’ and the education system was not helped by such increases, he said.

However, the Chatham and Clarendon School said it had no say when it came to appeals. It also pointed out that 10 of the extra places had been requested by the county council.

In a statement, it said: “We do not have any say over who is successful or not at the appeal process and the school has to take the pupils who have successfully appealed to gain a place.”

The school, like all others, was unable to turn down a pupil who had appealed and subsequently chose it. The school had 96 appeals this year, with 71 upheld but only 50 chose a place.

However, the expansion of grammar schools through the appeals system has been become a sensitive issue.

Cllr Paul Carter, the Conservative leader of Kent County Council, said he feared a dilution of standards.

He said: “I think you have got to be careful that you don’t dilute the specialism of grammar schools, which are there to provide a learning environment for the highly academic students.”

While the county council aims for about 25% of pupils to go to grammar, the figure stands at nearly 32%.”