"S'okay, Miss. I'll catch up later," says Kelly, before resuming her chat with Sam. Why do my pupils keep doing this? It's almost as if Kelly thinks she can store me and play me back later. I'm part of her DVD collection. She thinks she can pause me and watch me tomorrow, or whenever fits in for her.
It does make sense, now I think about it. Children spend twice as much time looking at screens as they do in the classroom, according to Consumer Kids, a new book by Ed Mayo and Agnes Nairn. On average, British children spend more than five hours a day - every day - watching television, playing computer games or online. On top of that, there's the tiny screen that flickers with the promise of popularity: the mobile phone.
About 90 per cent of teenagers and 60 per cent of five-to-six year-olds have a television in their bedroom. Two thirds have a games console. Young people's bedrooms have become "high-tech media bedsits" with more gadgets than a whole family would have had a generation ago.
Mayo and Nairns focus on how big business is using these new media to sell stuff to children, often dodging the need for parental permission. If you were nine and you wanted a stuffed pink horse, you would tick a box that said your mummy and daddy were OK with this, wouldn't you?
If I think about that for too long I will go mad. When I look at Kelly and Sam, though, I don't just think of marketing strategies targeting kids. I also wonder how more than five hours a day in front of a screen might be affecting their perception of teachers, of lessons - in fact, of everything.
This is the "Save to watch later" generation. We may worry about children being passively slumped in front of the television, and of course this does happen. But they have more control over what happens on screen than ever before.
They can design their own homepage, upload pictures, complete surveys for money as well as collect and delete friends. Above all, they can put it all off until tomorrow when it will still be there.
It won't, though. If you witness something amazing, such as a prancing horse, that experience can never be recalled. What is more, the effort to record it can destroy the moment itself. You can be so lost in trying to capture the experience that you didn't really have it.
The sense that reality can be stored and repeated is an illusion, and a powerful one.
We repeat things for our pupils more often than is necessary, and sometimes it's worth reminding them that a lesson is a live event. They look surprised when you tell them: "This explanation of your homework is a one-off. You can't play it back later if you chatted through it the first time."
It can also be fun to play with the differences between live and recorded reality, and the remote control can help. I sometimes use a TV remote in class on children who are about to make a speech or act out a scene, pressing Play to let them start. Even the cool ones, who professed to find this a bit lame at first, now fight over the chance to press Pause. They like to have a measure of control over reality. They're used to it.
Catherine Paver, Writer and part-time English teacher.