Frozen magnetism

Teaching magnetism and the Earth? Have you tried the ELI 'Frozen magnetism; preserving evidence of a past magnetic field in wax'? This activcity is a demonstration of how the evidence for the magnetic field around a bar magnet may be preserved, even after the magnet has been removed. This gives an analogy for the three- dimensional magnetic field of the Earth, with a North and a South Pole.
This is one of many Earthlearningideas in the Earth energy/processes category.