Lesson Summary
In this lesson, students will discover several properties of and uses for magnets. They also will have an opportunity to generate questions and to voice the ideas they have about magnets.
Teacher Background
Magnetism is a mystery in the natural world – it can levitate objects, act through solid objects (including human hands), and pull on things without touching them. It is what makes electric motors spin, loudspeakers and earphones work, refrigerator doors stay closed, and television, video recorders, and all household electricity (produced by electric generators, which use magnets) possible.
All permanent magnets contain either iron or nickel, or cobalt, or a combination of these elements. Not all metals are attracted to a magnet – a fact that confuses students. For example, aluminum foil is not magnetic, but it looks somewhat like steel, which is magnetic.
The flexible magnets used in this unit are primarily made of rubber or plastic with tiny particles of iron or ferrite, a class of materials containing iron. Magnetic recording tape is similar to this.
Some students will want to know why only certain metals are attracted to a magnet and why some seemingly nonmetallic objects also are attracted. Challenge students by asking them, “How can we find out?”
Set-up/Management Tips
- Prepare and rehearse the teacher demonstration listed in Step 1 in the Procedure section.
- Decide how you will distribute materials for each group and prepare materials for distribution.
- Prepare chart paper to record “magnet characteristics.”
- Keep magnets at least 12 inches away from computer disks, calculators, and audio tapes. The information on them can be erased by magnets.
Literacy Support
Teach students how to write reflections. Make sure they include why and how they came to their conclusions.
Scientific Vocabulary
The following words are key vocabulary words that will be introduced in this lesson and reinforced throughout the unit:
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