Under the No Child Left Behind law, that means that they have to take steps to improve student test scores.

NPR: Teachers at Troubled School Face Job Loss

Feinberg knows that she and the school face tremendous pressure to improve the test scores of the city's most challenging students.

NPR: For Charter Schools, New Orleans Is Citywide Lab

Over the decades, its system has helped countless students improve their test scores, and Kaplan wants to take its reputation for success to broader fields.

CNN: Kaplan is starting an online college -- minus the keggers

It pointed out that two school districts in Brooklyn are experimenting with a performance-related pay pogramme, which gives rewards to teachers and principals in schools where test scores improve.

BBC: Papers criticise 'NYC exam scam'