Funding for disadvantaged pupils has helped children in Sutton improve their grades.
Government figures show 42.7 per cent of children from poorer backgrounds in Sutton got five or more A* to C grades at GCSE last year compared to 39 per cent in 2012.
Pupil Premium, a system that gave extra funding to schools with more pupils from poorer backgrounds was introduced in 2012 and Carshalton and Wallington MP Tom Brake said the statistics show the initiative is working.
He said: "This is further proof Pupil Premium is transforming the chances of pupils across the country.
"We are increasing the pupil premium budget to £2.5 billion this year as well as extending the policy to three and four-year-olds. The party has already made sure from September all infants will receive free schools meals, so there can be no doubt that the Liberal Democrat’s priority lies in helping all pupils achieve their potential.
"School leaders are using funding more effectively, tracking the progress of eligible pupils more closely and reporting outcomes more precisely than before. I am confident that with the increase in the budget, next year we will see even better results in Sutton."
Carshalton High School for girls received funding in the scheme. Headteacher Fiona Crump said: "The funding allows us to help students that are eligible for Pupil Premium overcome any barriers they might face so they make excellent progress."