A Teesside school has doubled its pass rate for GCSE maths by using a virtual teacher to help pupils.
For the past 18 months, the online maths tutor has been trialled by children at Acklam Grange School in Middlesbrough with excellent results.
The ConquerMaths.com's "teacher" works out problems on screen before setting questions and marking them online.
David Cook, a teacher at Acklam Grange, said the system was so popular, pupils even logged on on Christmas Day.
The virtual lessons supplement traditional classroom learning, but can be watched again by pupils via any internet-connected PC.
Acklam Grange head teacher John Bate said: "It is incredibly effective at engaging children in maths. It's made mathematics accessible to the whole range of ability of our students."
ConquerMaths has been such a hit in Middlesbrough that another 40 schools are now looking at incorporating it into their maths curriculum.
Mr Cook added: "It's having a big effect on the kids who are using it, I would like to see it made available to every pupil in the country.
"We had 235 students choosing to log in at home to do revision on the day before an exam."