This is an activity about the declining strength of Earth's magnetic field. Learners will review a graph of magnetic field intensity and calculate the amount by which the field has changed its intensity in the last century, the rate of change of its... (View More) intensity, and when the field should decrease to zero strength at the current rate of change. Learners will also use evidence from relevant sources to create a conjecture on the effects on Earth of a vanished magnetic field. Access to information sources about Earth's magnetic field strength is needed for this activity. This is Activity 7 in the Exploring Magnetism on Earth teachers guide. (View Less)

This is an activity about the magnetic fields of the Sun and Earth, and the interplanetary magnetic field, or IMF. Learners will engage in a question and answer dialogue, make connections using bar magnet examples and overhead transparencies, and... (View More) ultimately write an assessment of concepts learned. This is Activity 1 in Session 3 of the Exploring Magnetism in the Solar Wind teachers guide. (View Less)