Manchester is risking a slip in its test results by pressing schools to take in challenging students.
The city's approach has been praised by the Department for Education and Skills and is expected to be copied by other education authorities.
The Government has been urging schools to become more inclusive and has made this one of the chief aims of its Children Bill. However, many headteachers have complained that there is little incentive for them to do so when their performance is judged on test results.
Education officials in Manchester have now developed a "kitemark" for inclusion which they want all the city's schools to achieve within the next three years.
Schools will only gain the "Manchester Inclusion Standard" if they admit children from all sections of the community and involve them in all activities. They are less likely to achieve it if they do not take on pupils excluded from other schools, refugees or children with severe learning difficulties.
Mick Waters, chief education officer, said: "There is a real tension between inclusion and attainment because schools are measured on their successes with tests. We are determined to put inclusion on a level with attainment."
The inclusion standard was developed in conjunction with Manchester university and piloted over the last school year. Four secondary and 12 primary schools have already gained the award and a further 45 plan to get it in the next year.
Whalley Range school is one of the first to achieve the standard.
Dame Jean Else, the head, said it took three months and led teachers to think carefully about the way they cared for gifted and talented pupils as well as those with English as an additional language.
Inspectors declared Manchester's GCSE results "unsound" in 2000 because the city's schools had removed up to 300 persistent truant teenagers a year from their registers.