London, March 24 (IANS): Do you force your kids to spend too much time on maths and science? Researchers have found that just an hour of homework can produce very good results.

The findings published in the Journal of Educational Psychology added that doing homework alone and regularly produces the biggest knowledge gain.

"Our data indicate that it is not necessary to assign huge quantities of homework, but it is important that assignment is systematic and regular, with the aim of instilling work habits and promoting autonomous, self-regulated learning," said co-lead author Javier Suarez-Alvarez from University of Oviedo in Spain.

"The data suggest that spending 60 minutes a day doing homework is a reasonable and effective time," Suarez-Alvarez added.

The study involved 7,725 students with a mean age of 13.78. Girls made up 47.2 percent of the sample. The students were given questionnaires asking how often they did homework and how much time they spent on various subjects.

Their academic performance in maths and science was measured using a standardised test. Students whose teacher systematically assigned homework scored nearly 50 points higher on the standardised test.

Students who did their maths homework on their own scored 54 points higher than those who asked for frequent or constant help. The curves were similar in science.

While some teachers assigned 90-100 minutes of homework per day, the researchers found that the students' maths and science results began to decline at that point.

And while they found a small gain in results between 70 and 90 minutes, "that small gain requires two hours more homework per week, which is a large time investment for such small gains", Suarez-Alvarez pointed out.