Magnets & Motors
Lesson 5
Building A Compass
Students learn about the characteristics of a magnetic compass.
3. Lesson set up and Management
Planning and Conducting Investigations: Plan, conduct, and evaluate scientific investigations, using appropriate equipment, mathematics, and safety procedures (IN02 2.1.2).
Communicating: Communicate scientific procedures, investigations, and explanations visually, orally, in writing, with computer-based technology, and in the language of mathematics (IN05 2.1.5).
A compass can be constructed by suspending a magnet so that the magnet is free to rotate.
3. Lesson set up and Management
Materials:
In some cases, the compass needles become de-magnetized or magnetized with reverse polarity. Be sure to check that all of the compasses are pointing in the same direction by laying them down in a row on a flat surface.
Student Management:
Have students remove any objects from the working area (watches, rings, etc.) that may affect compass magnets (and therefore the accuracy of compass readings).
It is very wise that the teacher build a demonstration straw compass ahead of time because building this compass can be very frustrating for students.
Save the student straw compasses for use during the next lesson.
Writing:
Ask students to think about and write other ways to make a compass.
Reading:
Have students read and interpret a map of the world showing explorer routes. Focus student attention on the role compasses played in their expeditions.