Most students will be aware of the presence of the Earth's magnetic field having viewed the needle of a compass as it is rotated.  Many will also have seen a generator in action and noted the electricity generated by the movement of a wire in the vicinity of a magnet.  However, they may not be aware that the Earth's magnetic field is also capable of producing electricity similar to that from a generator. 

This may be easily and simply demonstrated with the Earth's Magnetic Field Detector.  By rotating the detector through the Earth's magnetic field, an emf may easily be generated.