Bradford Grammar School bosses are shrugging off the recession and ploughing ahead with a £4 million campus redevelopment – thanks to two massive cash injections from well-wishers.

The scheme is being backed by a mystery donor who anonymously gave the school more than £1m last summer, and a further gift of US$1m (almost £600,000) from former pupil Roger Evans, a Bradford-born businessman who now lives in America.

A planning application has been submitted to Bradford Council to build a three-storey building dedicated to chemistry and social sciences on the car park of the existing Kenneth Robinson Building.

A large atrium-style structure would be built to provide access to the science building and the Clarkson and Kenneth Robinson buildings.

The Kenneth Robinson building will be refurbished to create an entire floor for biology lessons and another for physics.

The library and main building to the east of the school site, off Keighley Road, Bradford, will be connected to the new central atrium by a glass ‘learning link’ corridor.

Head teacher Stephen Davidson said the school was in a good position to expand despite difficult economic conditions.

In the latest edition of the school newsletter he writes: “The Governors have long held the belief that Bradford Grammar School should not borrow money for capital development – we must not mortgage our future.

“I sincerely hope that everyone associated with our school will share my own enthusiasm for the plans which will allow us to fulfil our academic, pastoral and administrative aspirations for many years to come.” Mr Evans’ donation is the second time he has dug in deep to fund improvements at the school.

He flew in from the United States for the grand opening of a new sixth form centre at the school in 2001 after he made a similar donation and was nicknamed the ‘million dollar man’.

Subject to planning approval, construction work will start at the school this autumn and is expected to be completed in September, 2010.