Governors of Kent’s first academy school have insisted it is making progress despite a highly critical inspectors' report that says pupils are not getting an acceptable education.

Ofsted has placed the Marlowe Academy in Ramsgate in special measures following an inspection last November which graded its effectiveness and ability to improve as inadequate.

The school was the first in Kent to become an academy under the previous Labour government’s programme aimed at transforming the fortunes of the country’s poorest performing schools. It was built at a cost of £30m.

Since then, it has had a chequered history and although it has seen a rising number of pupils passing five or more GCSEs, Ofsted says standards remain "well below the national average" and students’ progress is "neither rapid or secure enough to compensate for low attainment on entry."

They said many year 10 and 11 pupils had a reading age that was at least two years below their actual age League tables published in January revealed that 20% of pupils passed five or more GCSEs in 2011.

The school has a high number of children on free school meals - 35% - and around one in four has special needs.

The report says learning is ineffective because of low expectations and lessons that lack challenge.

It says external help for leaders and managers have had "too little impact" since the previous inspection and that absence rates and a high drop out rate in the sixth form present "a significant obstacle to students’ achievements."

The school was set up with the help of the former boss of Saga, Roger De Haan, who acted as the main sponsor.

He remains the chairman of governors and in a letter sent to parents states the inspection came at an unfortunate time because a new leadership team had only been in place for a short period.

The school announced recently it had appointed a new principal to take over from interim head Carl Wakefield.

He was brought in after the unexpected departure of Ian Johnson, who left in September.

Cassie Ellins is due to take over the running of the school shortly and Mr De Haan said he was confident that under her leadership "academic results this year will show significant improvements."

On the plus side, Ofsted commended the school for the support it gave to the personal development of students and the "lively promotion" of performing arts to boost self esteem and build community links.

Roger De Haan, Marlowe Academy chairman of governors, said: "I am disappointed.

"Our mission, set out at the time we became an academy, was to become an academy focusing on vocational subjects. That served us well in the early years. What we have not done is respond quickly enough to the National Challenge where schools were required to become more academic. The school struggled in making the transition quickly enough."

He added that Ofsted had not taken into account changes the school had made at the time of inspection, including a new team drafted in to help to strengthen leadership.

"The new team is reporting that we will make significant improvement in academic performance next year and are predicting a 50% improvement in English and maths at GSCE."

He denied the academy programme set up under Labour was a failure and the costs had been excessive in relation to improvements.

"It was a good investment. The old Ramsgate School was a seriously awful place – the children had no confidence or ambition. The children we now have are very different."