The national testing programme evaluates mathematics, language and other skills of grade four or grade eight students in alternate years, by testing whole classes.
Results have helped the government target the worst schools for remedial programmes to improve quality. New results show the poorer schools making most improvement.
The tests, designed to measure how much curricular material students can master, showed a rise from 50 per cent to 60 per cent. In the poorer government-funded schools, there were rises of 23 per cent in Spanish and 30 per cent in maths