Three of 13 teachers at Holden Lane high, Stoke-on-Trent, had their applications for responsibility payments on the upper pay scale (UPS) rejected in January. They lost their appeals in April.
Last week, 40 members refused to cover lessons at the 1,200-pupil school.
The action was continuing as The TES went to press.
The union said that all eligible staff should have been considered for UPS3. But head Lynne Hardcastle said she did not want teachers to go through unnecessary rejection.
The NASUWT has dealt withUPS3 disputes at 20 schools in England and Wales.
Industrial action has been taken in six.