Activists have started a campaign to block plans to build houses and construct a football pitch on parts of a school’s playing field.

Varndean College in Brighton wants to install an Astroturf pitch, eight 4.5 metre floodlights and ten houses on the land near Surrenden Crescent.

It recently submitted a planning proposal to build a new two-storey STEM (science, technology, engineering and maths) centre with parking. The project would cost about £3.2 million. The sale of the land for housing development would fund for the football pitch.

Green Varndean Action Group objects to the plans because of loss of urban green space, noise pollution and impact on wildlife. The group held a demonstration near the school in Surrenden Road on Wednesday to publicise its new campaign to protect the green space.

It aims to nominate the field to be an Asset of Community Value meaning the land is subjected to significant protection from development.

Spokesman John Davies said: “We asked residents to fill in questionnaires about their attitude to the green space.We also asked motorists to sound their horns if they drove on the route specifically to see the greenery and unique view.

“About a quarter of motorists indicated they did. We have received more than 300 responses to our questionnaire so far.

“We approached Brighton and Hove City Council to ask if we can nominate the land to be an community asset. If successful, the land has more protection from development, and the community can decide what to do with it.

“Although the land is privately owned, however, it’s always permitted public access, so therefore we can put in a nomination. The questionnaires will be presented to the council to prove our case.

“We are supportive of the school to improve its facilities, but we fear it may breach the city plan to preserve urban green space which is vital to future generations.”

Principal Dr Philip Harland said: “The city is facing a housing crisis and there are significant constraints in identifying new land and it’s crucial to meet the need. We have taken advice from experienced planning consultants to ensure that the scheme we have proposed gives due care to our environment.

“The 3G pitch will increase the amount of playing time for both college users and the community. This development has the full support of Sport England and is consistent with the city’s playing pitch strategy. The fact is we need better educational facilities for the young people of this city and beyond.”