Researchers who took part in the Third International Maths and Science Study discovered that English pupils who were given a lot of maths homework easily outscored children who spent little time studying at home.
Nine-year-olds taught by teachers who set maths homework three or four times a week scored substantially more than those who did little or no homework. And 13-year-olds' maths scores rose progressively according to the number of hours of homework set.
These findings will almost certainly be used to support the Government's plan to standardise the amount of homework that schools demand from September 1998. Minimum levels of 30 minutes a night for older primary children and 90 minutes for secondary pupils are said to be under consideration.
But the National Foundation for Educational Research, which has been analysing the data on the 10,000 English children involved in the study, has warned that the figures should be handled with care. The researchers believe that it is not only the amount of time spent on homework that is important, but how the teacher builds on the tasks and activities done at home.
"In the secondary school in particular the answer isn't just to issue more homework - the teacher has to mark it and provide feedback on it," one of the researchers Wendy Keys said. "It seems that you have to build lessons or class discussions around the homework if it is to be really worthwhile."
Her view appears to be borne out by the statistics which show that pupils who "always" got feedback on homework outscored those who "rarely" had any follow-up.
The value of feedback on homework was, however, less evident in the science classes. And though there was a link between the amount of homework and the science test score it was also less clear-cut.
The two NFER reports to be published next week, which are based on test results and questionnaire responses collected in 1995, complement the two earlier reports generated by the 40-country TIMSS. Data on the 13-year-olds' maths and science performance were published last November and the nine-year-olds' results were announced last month.