Lego Dacta's eLab teaching kits for exploring energy include an array of intriguing components. In the Renewable Energy set, pupils use Lego motors as electricity generators in windmills and waterwheels, while a new capacitor brick wired into the system shows them how this kind of energy can be stored. They can measure the energy of these devices - by measuring the distance the stored energy can lift a mass. The Lego Solar Cell, made by Shell, can be used to make a sun-powered buggy, and again show the capacitor in use as a store when the sun goes down.
What's attractive is not just the Lego material, but how so many aspects of the topic can be covered even when time is short. The kit has unusually efficient motors. Turning one wired to another shows a single turn of one motor produces almost a full turn of the other. When pupils try to generate power for two motors, they feel the increased torque and can count the turns to measure efficiency - as the worksheet says, "you can't get something for nothing". The teaching notes are a credit to the hardware: creative contexts, structured activities and lots of hands-on.
In the computer department there is a control and monitoring system based on an intelligent brick called the RCX. This microprocessor device has connections for three motor or lamp outlets and three sensors and can be remote-controlled by an infra-red transmitter. It is similar to Lego Mindstorms, a home robotics system, but is designed to develop ideas about control progressively. Software called Robolab unfolds level by level to offer more and more control capability. It is surprising how much easier it makes classic control projects - such as a light-seeking buggy, a passenger lift or a greenhouse. In fact, it makes many old style projects attainable. At the heart of this software lies LabView, a state of the art monitoring package used in industry. New this year will be a science edition of the Robolab software, where the same core hardware gains the new trick of being able to measure and display temperatures, light levels and even oxygen levels. The new software features a graph display where you might see how steady is the greenhouse temperature. There are also software tools to analyse the graphs and another first: you can write up your project in the software and then save it as web pages. There's an unusual completeness about Lego Dacta's data logging kit: it works with LogIT range sensors, is self-powered and offers opportunities for control and monitoring projects which to date have been beyond reach.
There are several pack options in the eLAB series. The suggested set-up for a whole class is one Energy, Work and Power set (pound;185.50) and three Renewable Energy sets (pound;104) plus two teaching materials (pound;18.50 each). The Solar Cell (pound;26) and capacitor (pound;11) are available to supplement these and make for some entertaining classroom displays.
ROGER FROST Roger Frost is a member of The Science