David Black smiles a school-masterly smile, and trots over the same ground, aims a few pertinent questions at individuals and risks a joke before ploughing on with the syllabus.
What makes this old-fashioned teaching odd is that pupils and teacher are 200 miles apart: the class is in Cardiff on the south east coast, and David Black in Anglesey, on the extreme north-west tip of the Principality. He and his pupils communicate via the VC7000, a stand-alone video conferencing system.
Simply, the VC7000 is a television screen with a video camera and microphone mounted on it. Images and sound are digitised and carried by telephone line to anyone else with a similar set-up. As in a "proper" lesson, the interchange is genuinely two-way.
The sound (as good as a cheap television) comes through built-in speakers, so there is no need for telephone handsets. Once seated within camera range, the pupils do not need to modify their behaviour in order to accommodate the technology - except perhaps for improving their enunciation.
All this is made possible by BT's integrated services digital network (ISDN). From the user's point of view, this is a fancy telephone line that can shift digitised data (picture, voice, fax or whatever) 30 times faster than a normal line, enabling real-time, full-screen (if slightly jerky) video conferencing.
It costs Pounds 400 to have an ISDN line installed, and a further Pounds 84 for the quarterly rental. Connection time is charged at the standard peak rates tariff, but having two-way communication doubles the charge. The VC7000 costs a further Pounds 5,000, so it is a pricey investment but can still be cheaper than employing specialist staff for minority subjects.
The Glantaf school, for example, would not normally be able to afford to offer sociology to just five students. But it can buy in a distance learning package from Gwynedd for Pounds 490 a student a year. For this they get Mr Black's fortnightly video-lessons, complemented by some lengthy sessions with a peripatetic tutor, and underpinned by the usual reams of support material. But, surely, video conferencing is a second-best substitute for having a "real" teacher? The Glantaf students were unanimously upbeat. Of course, they "wouldn't be happy if it was like this for all our subjects", but they also saw the positive advantages of distance learning.
Sara Rees says: "If it was the only way I could do a subject I really wanted to do such as drama, then this is the way I'd do it." Nia Pritchard admits: "I had my doubts at first, but that was just my usual fears about modern technology dehumanising everything. Now I know it's up to me to make the most of it."
Michelle Coles says: "It's a sort of self-discovery. You find out it's you who's got to do the work, and discipline yourself - good preparation for college and things." Strangely, they do not treat this sci-fi schooling as a big deal. "It doesn't make much difference to me. I treat it as a normal lesson," Beth Jones says.
David Black undoubtedly knows his class and even argues that video conferencing is in some ways better than being in the classroom. "The screen helps them to concentrate on the teacher, and the teacher is highly conscious of how attentive the pupils are, who's taking notes, who looks confused, who's being distracted." He has 60 pupils using video conferencing dotted around Wales, others in Shropshire, and plans to extend the programme into Northern Ireland and to any school in the UK with an ISDN line.
Geoff Davies, deputy head at Ysgol Dyffryn Taf in Whitland, Dyfed, says: "Video conferencing is a fantastic development with enormous potential, especially for schools in rural areas." He was in school. I was talking to him from the centre of the Dyfed satellite project in Newcastle Emlyn. We were video conferencing via Intel's Proshare, a Pounds 1,850 software and peripheral package that converts an ordinary PC (providing it is powerful enough) into a means not only of exchanging pictures and sound on an ISDN line, but also of sharing computer applications.
In a smaller window, I could see Mr Davies, while most of the screen was occupied by the program that we could work on jointly, taking turns to control the mouse. We did some giggly word processing, but Dr Annette Temple who heads the centre is already convinced that the technology will revolutionise the in-service training she can offer.
She says: "I can visit schools without leaving my office, giving on-screen help with software problems." Similarly, teachers do not need to trek to teachers' centres for costly training sessions now the tuition can be delivered direct. Dr Temple also uses the system to download the meteorological data in her archive, making it accessible to schools in new ways.
But what particularly excites her about the technology is the opportunity it offers teachers anywhere in the country to establish their own informal networks, sharing expertise and data. "We're just taking our first tentative steps now," she says, "and don't know which direction developments will take us in. What's important is that teachers are now given the opportunity to decide for themselves how useful this technology vmight be." They might start by noting that five sociologists in Cardiff have already made up their minds.
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