Teachers at a west London school are recording parts of their lessons on to video so pupils can play them back if they have any misunderstandings.
Staff at Villiers high in Southall have so far filmed about 30 clips using digital camcorders and edited them on the school's computers.
Each of the short videos focuses on a different skill or concept and lasts up to 10 minutes.
The recordings are loaded on to the school's computer network so pupils can play them whenever they want. From next term students will also be able to watch them at home via the school's website.
Juliet Strang, headteacher, said she had been eager to introduce the system because pupils had different learning speeds.
The ability to replay lessons was particularly valuable at a multicultural school like Villiers, she said.
More than 90 per cent of its students speak English as an additional language and around 100 of its 1,200 pupils are refugees.
"All teachers can describe the frustration of giving instructions to a class and then two minutes later hearing a student asking 'I don't know what I'm supposed to do'," Ms Strang said.
"The advantage of this scheme is that students can access the material any number of times, anywhere and at any time."
Video is becoming an increasingly common teaching tool but Villiers is believed to be the first school to use it in this way for all subjects across the curriculum.
Each department has been asked to draw up a list of topics to film each term and teachers will be given one to two hours to make each video.
Ms Strang launched the system last term by making a short science video herself about a model of the atom. The rest of her staff spent a day-and-a-half training how to use the camera equipment and the editing software on the school's Apple Macs.
The first batch of films was then presented at a "premiere party" in the school staff room and news of the scheme has spread quickly to other London schools. One teacher who contacted The TES said he feared it would be used to cut back on teacher numbers, as teaching assistants could play the clips to classes.
John Bangs, head of education at the National Union of Teachers, said that concerns were understandable but added: "The system sounds like a wholly proper use of technology and a good revision tool. It is just a sign of the times that teachers believe that substituting videos for themselves is a real possibility."
Villiers has insisted it has no plans to replace teachers with video recordings and sees them solely as tools to aid teaching and revision.