• Observe students during the activity and notice their ability to:
  • Successfully reveal a magnetic field
  • Make observations and record data
  • Identify questions about electromagnetism
  • Communicate ideas and findings using scientific language and representations
  • Work collaboratively as part of a small group
• Use the "Find the magnetic field" answer key to review worksheet responses
• Students should complete the "Magnetic fields competencies self-assessment"

• Check out the "Build an electromagnet" activity to continue exploring electricity and magnetism
• Try the activity again, but this time have students move the compass through the magnetic field and observe the reaction of the compass needle. Does it line up along the pattern in the filings?
• Students can make their own basic compass. Have them rub a needle against the bar magnet several times and then stick the needle through the top of a cork. When the cork is floated in the jar of water, the needle will orient itself with the Earth’s magnetic field
• Experiment with how ceramic magnets affect the iron filings

• Draw the magnetic field that surrounds a bar magnet and it appears as curved lines that move out from the north pole and return to the south pole
• The magnetic field is strongest inside the magnet. Surrounding the magnet, the field is strongest near the poles
• A magnetic north pole will attract the south pole of another magnet and repel a north pole

• The Earth has a magnetic field that is created by an inner core of iron at the planet’s centre. Earth’s iron core is as hot as the Sun’s surface, but the immense gravitational pressure is why the core is in solid, not liquid, form
• Surrounding the solid iron core is a 2,000 km thick layer of iron, nickel, and other metals. Because the pressure isn’t as intense, these metals are fluid. Convection currents form in this layer and the Earth’s spin also causes swirling movements in the molten metal. This flow of liquid iron generates electric currents, which in turn produce magnetic fields. 

• Think of the Earth as having a gigantic bar magnet buried inside, creating north and south poles. The magnetic field extends far out into space, shielding our planet from the solar wind. The interactions between Earth’s magnetic field and these charged particles coming from the Sun cause the Aurora Borealis or Northern Lights.
• The needle of a compass is a tiny magnet. It is affected by the Earth’s magnetic field and lines up in a north-south orientation. The red side of the needle always points to the Earth’s magnetic north pole. The first navigation compasses were designed according to the same principle: a chunk of lodestone would be tied to a piece of wood and floated in water. 
• This imaginary bar magnet that is in the Earth does not run exactly north/south. It is “positioned” slightly off the Earth’s axis, which is why our magnetic North Pole is in a different location than the geographic North Pole.

Grade 7 Science - Content

• Electromagnetism

Grade 7 Science - Curricular Competencies

Questioning and predicting

• Demonstrate a sustained intellectual curiosity about a scientific topic or problem of personal interest

Planning and conducting

• Collaboratively plan a range of investigation types

Processing and analyzing

• Use scientific understanding to identify relationships and draw conclusions

Communicating

• Communicate ideas, findings and solutions to problems

Grade 7 Applied Design, Skills, and Technologies - Content

• Power technology
• Forms of energy
• Devices that transform energy

Grade 7 Applied Design, Skills, and Technologies - Curricular Competencies

Prototyping

• Identify a question to an answer or a problem to solve through scientific inquiry

Testing

• Gather peer and/or user and/or expert feedback and inspiration
• Make changes, troubleshoot, and test again