The pulling power of the magnet is growing stronger all the time. Roger Frost reports
If there's a force keeping the techno world working, it's magnetism. In videos, televisions and computers this magic force is at work in so many things electrical. You might also know that a fridge door is kept shut with magnetic power, as well as a touch of personal willpower too.
So we need to teach children about magnets, and about poles, attraction, compasses and magnetic fields.
Getting them interested shouldn't be hard because there are some excellent resources about. Some are just so good that if you get them for school you'll want to take them home.
It's hard to generalise about what schools need. It might be a class set of magnets or a mixture of different ones. But all schools will want a few really powerful ones because all that "magnetic force at a distance" is too mind-blowing to miss.
The Magic Penny Set consists of a booklet of ideas, a handful of coins and two magnets so strong that they snap together with a crack.
With it you can make a pyramid with a dozen pennies on their edges, or make a penny roll along a wire coathanger. You can "launch" a penny from one end of a magnet to the other or make a hanging penny chain and then spin the bottom coin by blowing on it.
The tricks will make excellent demonstrations and appeal to conjuring-types. Of course, you can do most of this with any magnet, if you know your stuff. However, the built-in booklet, while written for adults, does throw you a few surprise tricks and builds your conjuring confidence. The set also makes a fine gift and it's especially good that the proceeds go to hospital charities.
Dowling, the magnet maker, offers an impressive collection of kits. For example, its Giant Horseshoe magnet is a no-mistaking-it magnet for primary schools and its colourful Primary Magnet Wands invite probing at all sorts of magnetic suspects. They are quite powerful too and work well with Magnetic Marbles, which roll over them amusingly. The marbles form chains and circles and they make a mean game when they stick instead of bounce. You can also dip a magnet into some Counting Chips - light, see-through coloured circles which are more fun than paper clips and get picked up by the dozen.
Dowling has all sorts of kits and permutations, some for schools and some for toy shops. Secondary schools need not shy away from all the colour: Floating Magnet Rings, the Magnet Motor kit, and the Electric Motor and Generator kit will make stimulating show pieces.
You can also buy rolls of rubberised Magnet Strip, the actual stuff in the fridge door seal. In addition to science you can use it for technology projects and to stick objects to your filing cabinet.
Some of Dowling's Wonderboard kits, which have a metal sheet with stick-on Magnet Strip shapes, will find a classroom use. Using them the children can design a castle or a palace or an insect or butterfly with little chance of it being knocked and spoiled.
For the library, Dorling Kindersley's First Book of Batteries and Magnets is a good choice. The large pages and lovely pictures show how to make a floating turtle compass, a fridge magnet and a fun clown which bounces on two repelling magnets. There are plenty of home projects and a few ideas for school. You might, for example, show a magnet's field by hanging it in iron fillings and golden syrup.
As you browse through the catalogues, do note the materials the magnets are made from. Chrome steel magnets are cheap and fairly good but nearly all of the ones in the kits above are the very powerful ceramic or ferrite type. These keep most of their power if you drop them, but they are brittle.
For something formidable get an Alnico magnet and to sample power which is almost frightening, try a pair of small Neodymium magnets.
Your magnets will last longer if you store them so that they don't bang about in a tray. Keep them in matched pairs with opposite poles attracting or replace the "keeper", the piece of steel which channels and protects the magnetic field.
It's ironic that magnets are found in computers, televisions and videos, the very things that you have to keep far away from them: one glancing blow and your hard disc and tapes could easily be wiped. But then there's usually some irony to do with magnets, isn't there?
* Magic Penny Set
Retail price Pounds 19.99. Education price for two packs is Pounds 30 inclusive. All ages, Education Liaison, Brunel University, Middlesex UB8 3PH. Tel: 01895 2744000
* First Book of Batteries and Magnets
Pounds 6.99. Age 7-11 Dorling Kindersley,`9 Henrietta Street,Covent Garden, London WC2E 8PS. Tel: 0171 836 5411
* Dowling Magnets produces the Giant Horseshoe magnet (about Pounds 6) Wonderboard (about Pounds 10) Floating magnet rings (about Pounds 6) Primary magnet wand and magnetic marbles or counting chips (about Pounds 6) Rubberised Magnet Strip (about Pounds 3) Their toy shop kits include the Very First Magnet KitSuper Giant Horseshoe Kit Magnet Motor Kit Electric motor and generator kit (from Pounds 12 to Pounds 18)
* A selection of kits is obtainable through Commotion, Consortium, Galt, Hope, TTS, science museums and toy shops. Dowling Magnets, Lee Valley Technopark, London N17 9LN.Tel: 0181 880 4135. Stand H3