Magnetism; Electricity

My first real toy was an old brown horseshoe magnet, a piece of card and a bunch of iron filings. I've loved magnets ever since and particularly welcome Pam Robson's book. The well-illustrated approach is good; first you do an 'experiment' like using polar repulsion to propel a toy car, then you learn 'Why it works' (actually I'd prefer 'how'), and then you find some more things to do which use the same principle. Terrestrial magnetism and the compass are well explained and the different properties of permanent and electromagnets shown. From here it is but a short step to levitating magicians, acrobatic paperclips and the coin-sorting slot machine.

As much fun can be had with electricity, as long as you don't meddle with the mains. This message precedes everything in Baker and Haslam's book - which was actually written, it seems, by Alexandra Parsons. Simple circuits, elementary switches and morse-flashers all appear in well-pictured d-i-y detail, and the introduction of magnets in the second half permits the construction of challenging electric cranes and boats and trains. The complexity of these latter examples suggests that a cooperative approach will be the most rewarding. This is a bright and not dissimilar pair which will well serve any junior or middle school project.