Two grammar schools could face funding cuts as almost half their Year 7 places are empty this September.

A dip in births a decade ago means Medway has 450 spare spaces for 11-year-olds, enough of an intake for two large schools.

Almost all are in Chatham, where schools, which are funded per pupil, could face steep cuts.

Worst-hit is the Bishop of Rochester Academy, which is already cutting about 30 staff.

The school’s admissions dropped due to population changes and publicity around its first-year GCSE results, which have since improved but were the third-worst in England.

It gave 107 offers - leaving 133 places (55%) vacant.

More surprising is the 130 vacant spaces at the town’s two main grammar schools.

Chatham Grammar School for Boys has 72 spare spaces (49%) while Chatham Grammar School for Girls has 58 (41%).

Some will be filled through appeals before September 1, but there are simply not enough pupils to go round.

Chatham Grammar for Boys head teacher David Marshall said: “I’m not surprised because we have, in the middle of Chatham, a demographic downturn.

“We’ve got children applying from across Kent to get into grammar schools so we have a slightly bizarre situation.”

But Mr Marshall said the school was already budgeting for lower numbers. It never reaches its 146 intake and is applying to reduce to 120.

He said: “Of course if you haven’t got 120 youngsters, which is what we bargain on, then every child under 120 is a loss of effective income to the school’s budget and could affect courses, but we’ve allowed for that.

“Although it looks catastrophic, there have only been one or two years in the last 19 where we’ve exceeded that number.”

The other under-subscribed schools this year are St John Fisher, Chatham (26% empty), Hundred of Hoo (25%), Robert Napier (23%), Walderslade Girls (3%) and Fort Pitt Grammar (1%).

Yet figures obtained by education adviser Peter Read showed some schools were heavily over-subscribed.

Brompton Academy turned away 84 first preferences, followed by the Thomas Aveling School, which turned away 43 and Strood Academy, which turned away 37.

Mr Read said population issues were partly to blame but the figures laid bare unpopular schools.

“People are voting with their feet,” he said. “The popular schools are becoming more and more desirable and so there are schools that a lot of people don’t want to go to.

“I’m afraid it’s called parental choice. It’s a bigger problem in Medway than across Kent because the area is smaller.”