Royal Borough deputy council leader Simon Dudley says Ofsted figures show the achievement gap between pupils from wealthy and poorer households is larger than the national average.
In 2011 the percentage of Free School Meal (FSM) pupils achieving five GCSEs grade A*- C including English and maths was 24.3 per cent. The number for non-FSM pupils was 66 per cent.
FSM is awarded to pupils from low income households.
This means there is a 41.7 per cent attainment gap in the borough. The national average is 28.5 per cent.
Cllr Dudley said: "It is clear RBWM is not achieving sufficient success in closing the educational attainment gap.
"I don't know why it's there but I want to find out and that's a question for all headteachers in the borough."
He hopes to remedy this by opening Holyport Free School, a non-selective boarding school independent of the council.
The 47-year-old banker is part of a group which has submitted a bid to central government for £15m of funding to flatten the former Holyport Manor site in Ascot Road and build a new campus for 500 pupils.
Cllr Dudley said they would ensure all pupils received the same education by having smaller class sizes of about 20.
A rival group also wants to take over the former Holyport Manor site and open a new school there. Developer Michael Shanly and his partner Daniela Szmigielska are part of a group which has put in an offer to buy the Ascot Road site from the council.
Their aim, along with fellow bid directors Emma and Nigel Barklem, is to open Beech Lodge School at the site in September.
For the full story see this week's Maidenhead Advertiser.
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