However, inspectors said that a minority of teachers were reluctant to accept that higher standards were achievable.
The study, from the Office for Standards in Education, found that the government programme has helped most schools involved raise expectations and broaden the range of experiences available to pupils. Where it was most effective, it has raised self-esteem among disadvantaged younsters, it said.
Inspectors, who visited 28 primaries, found that results at key stage 2 were improving at a higher rate in EiC primaries than in other schools nationally, and attendance has improved at five times the national rate since 1998.
The report found that learning mentors were having a positive impact on pupil achievements, and noted that partnerships with parents and the wider community had improved as a result of the initiative.
However, in four of the schools inspectors noticed that staff lacked faith in pupils' abilities.
They found "a pervasive blame culture and headteachers attributed low standards and challenging behaviour exclusively to the pupils' home circumstances".
There were also concerns that a small number of schools believed that the gifted and talented strand undermined equal opportunities.
David Bell, the chief inspector, said: "The programme has made a valuable contribution to social inclusion as schools have increased their awareness of the barriers pupils face and developed appropriate intervention strategies.
"The programme is starting to realise its potential but still more must be done if all its ambitions are to be fulfilled."