Students who visit Facebook or chat sites every day are more likely to fall behind in math, reading and science.

Teenagers who regularly play online video games tend to improve their school results, according to new research from RMIT University in Melbourne, Australia.

But school students who visit Facebook or chat sites every day are more likely to fall behind in maths, reading and science.

Associate Professor Alberto Posso, from RMIT's School of Economics, Finance and Marketing, investigated the results of testing by the globally recognised Program for International Student Assessment.

PISA tested more than 12,000 Australian 15-year-olds in maths, reading and science, as well as collecting data on the students' online activities.

Posso said video games could help students to apply and sharpen skills learned at school.

"Students who play online games almost every day score 15 points above the average in maths and 17 points above the average in science.

"When you play online games you're solving puzzles to move to the next level and that involves using some of the general knowledge and skills in maths, reading and science that you've been taught during the day," he said.

"Teachers should consider incorporating popular video games into teaching - so long as they're not violent ones."

Posso said teenagers who used Facebook or chat every day scored 20 points worse in maths than students who never used social media.

"Students who are regularly on social media are, of course, losing time that could be spent on study - but it may also indicate that they are struggling with maths, reading and science and are going online to socialise instead.

"Teachers might want to look at blending the use of Facebook into their classes as a way of helping those students engage."

Posso said it was important to recognise that other factors could have a major impact on teenagers' progress.

Repeating an academic year or skipping classes could be as bad or worse for scores than high use of social media.

Indigenous students or those from minority ethnic or linguistic groups were also at greater risk of falling behind than those using Facebook or chat every day.

The research, "Internet usage and educational outcomes among 15-year-old Australian students" has been published in the International Journal of Communication.