With Edison, students can make working electric circuits by arranging switches, bulbs and batteries and wiring them up with the mouse. It is a circuit simulator that is easy to use. A good place to start if you want to make more use of information technology.

Edison offers the usual components for electricity experiments: power supplies, resistors, potentiometers, meters and motors. There is an ACDC version with coils, capacitors, signal generators, signal analysers and oscilloscopes. You can put these in circuits and adjust them as if real. So when it’s time to do Ohm’s Law or to study parallel circuits, you will find all the apparatus working and present. If you make a short circuit, the wires go red and things give off smoke, a couple of clicks removes the “short” and repairs them.

You can do the basic experiments showing, say, how more batteries make lamps glow brighter or motors turn faster. You can show the meter readings in the circuit, the internal resistance of the batteries, and how changing the resistors changes their colour-coded bands, too. For clever stuff, put two sinusoidal generators into a loudspeaker, listen to the pulsing beats when the waves are out of phase and measure their frequency.

A big plus point is that the components are as you see them on the bench rather than as symbols, which gives students a perch on what they’re doing. They can also experiment without fuss or damage and get through more experiments than usual. Another bonus is that the work is what you would normally do; there is no need for special worksheets as there are countless experiments in the text books.

The program has ready-made experiments and problems giving clues on how you can set up circuits in advance. There’s a “macro” feature that records your circuit building and lets you add comments as if you were running a demonstration.

The minuses can be worked round: the parts are not labelled, so you do need a help sheet; they are small and need intricate mouse work; and the wires get into a tangle which is difficult to sort out.

That it doesn’t do circuit diagrams can be used to advantage. For example, students can copy and paste a circuit into a document and add a table of results. If circuit diagrams are important, packages such as Crocodile Clips do these well, while Edison seems the better program for learning principles.

Here, then, is a rare item - a genuinely interactive program. It is a tool for extending practical work and learning without labouring. Best of all, it can work on computer suites so old that schools don’t show them to parents any more.

However, if you can find a modern Internet machine, there’s a free demo waiting there - a service that must rate as a wonder of the “fabulous world of electricity”.

* Information and working demo of Edison available at: www.designwareinc. com * Crocodile Clips, PO Box 316, Edinburgh EH9 1BX. Tel: 0131 447 6438; Internet: www.crocodile-clips.comeducation