Recognising the need to understand computer-aided manufacture, the key stage 4 design and technology curriculum requires that pupils be taught how it is used in large-scale manufacture and in the production of single items and small batches.
What schools need, though, is something that bridges the gap between the simple control routines taught to younger children and the sophisticated and expensive equipment derived from industrial practice. Roger Twist, head of Damp;T at Brownhills Community School, Walsall, says costly machines may also give hard-pressed departments little value for money. He says: "I have shied away from buying an expensive machine because it would sit on the bench for long periods not being used."
It is to fill this gap that the Technology Enhancement Programme has developed the CNC Machine, a small cutting device that can be programmed to cut sheet material to a set design.
The more you look at the device, the more you admire the principles it embodies. The business end consists of a small cutter working on a table measuring 150mm by 240mm. It will cut two-dimensional shapes from a range of sheet materials - acrylic up to 5mm thick, aluminium up to 1mm. The controller is a small box with a keypad, which defines the direction and extent of the cut, with an LCD screen that gives prompts and shows what the machine is doing.
The controller is self-contained, so a pupil could disconnect it, take it away and programme it in class, converting a design on squared paper into a series of keypad prompts. The controller could then be brought to the machine to do the work.
It is possible to have more than one controller for the same machine, with pupils programming in their work and doing their cutting when the machine is available. Programmes are stored on a removable smart card. And because the card is a simple device made of standard electronic components, as Mr Twist points out: "Making cards can be a class project in itself."
The machine's strengths are its simplicity and low running costs. The obvious uses, Mr Twist says, "are in engineering, graphics and electronics and control - but there are cross-curricular opportunities too".
What it does, in effect, is offer not just a way of teaching the principles of computer-aided manufacture, but a solution to a host of design-and-make problems. Mr Twist believes it will be a boon to teachers and pupils of all age groups as an easy and accurate way of cutting acrylic sheet - a much-used material in design and technology classes. "It's so much better than using coping saws, where the blades break and the finish is rough."
The TEP CNC Machine costs pound;750 plus VAT. The memory chip for the smart card costs pound;1.50. The controller is pound;118. Orders and enquiries to Middlesex University Teaching Resources, Trent Park, Bramley Road, Oakwood, London N14 4XS. Tel: 0181 447 0342. Fax: 0181 447 0340