Rival groups are vying to open a new free school on the same Harrow site.
High schools from across the borough have joined together to propose a new secondary school on the site of Heathfield School for Girls, in Beaulieu Drive, Pinner.
Heathfield is due to close and merge with Northwood College in Hillingdon in September this year.
But the site also been earmarked for a new Church of England high school Bishops Ramsey School and the London Diocesan Board of schools.
The applications for the two free schools will go to the Department of Education, which will decide on which will get the site in Beaulieu Drive.
The department may give the go ahead to both applications, giving one the former Heathfields site and propose an alternative site for the other.
The Heathfield School for Girls site is the subject of two bids to create a new free school
A conglomerate of Harrow schools hope to set up the Pinner High School to help provide school places in and around the area.
Chris Livesey, headteacher at Nower Hill High School, said: “The schools in Harrow are committed to our local communities.
“We know that more primary school places are required and that more high school places will be required towards the end of this decade.
“We want new schools to be part of the successful Harrow family of schools. We also want the new schools to be for the whole local community.”
Under the plans the school would open in 2016, have 180 places a year for year 7 pupils and eventually provide for children from 11 to 18.
Schools in Harrow are also applying to create a new primary school on the soon to be developed Kodak site.
The Harrow View Priamry School would also be a free a school with 90 reception places to open in 2016 and involve the building of a completely new school building.
Rutinderjit Mahil-Pooni, headteacher of Kenmore Park Infant School, said: “Local schools have great experience of working in the communities that will benefit from these schools.
“The new schools would have curricula that motivate and stretch students while providing support to ensure that all children fulfil their potential.
“We are building on what we know works. We are ensuring that our proposals help children enjoy their learning and gain the skills and knowledge to succeed.”