Physics · 10th Grade

Active learning ideas

Magnetic Fields and Forces

Magnetic fields and forces are abstract and invisible, so active, hands-on exploration helps students build mental models they can trust. By predicting, mapping, and discussing magnetic behavior, students see firsthand how field lines behave and why poles always come in pairs.

• Common Core State Standards
• STD.HS-PS2-5
• CCSS.HS-RST.9-10.7

• 15–40 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Think-Pair-Share
• 15 min · Pairs

Think-Pair-Share: Field Line Prediction

Students sketch predicted field lines for two magnets in different configurations (north-north, north-south, one magnet near iron filings) before doing the actual demonstration. After seeing results, pairs compare predictions to observations and identify what their initial model got wrong.

How does the Earth's magnetic field protect us from solar radiation?

Facilitation Tip

During the Think-Pair-Share, circulate to listen for students who confuse geographic and magnetic poles, and gently redirect by asking them to trace a compass needle’s path on a world map.

What to look for

Provide students with two bar magnets. Ask them to predict and then demonstrate how the magnets will interact when brought together in different orientations (e.g., north to north, north to south). Have them draw the setup and label the poles involved.

• Understand
• Apply
• Analyze
• Self-Awareness
• Relationship Skills

Activity 02

• Gallery Walk
• 40 min · Small Groups

Lab Investigation: Mapping Magnetic Fields

Small groups use compasses or iron filings to map the field around bar magnets, horseshoe magnets, and two magnets in different orientations. Each group creates a labeled diagram and writes a summary of one pattern that surprised them.

Why do magnetic poles always come in pairs (North and South)?

Facilitation Tip

In the Lab Investigation, remind students to keep iron filings contained and to use a ruler to maintain consistent distances when measuring field strength near poles.

What to look for

On an index card, ask students to draw the magnetic field lines around a bar magnet. They should label the poles and indicate the direction of the field lines. Include one sentence explaining why field lines do not cross.

• Understand
• Apply
• Analyze
• Create
• Relationship Skills
• Social Awareness

Activity 03

• Gallery Walk
• 25 min · Small Groups

Gallery Walk: Real-World Magnetic Field Applications

Stations feature images and short readings on Earth's magnetosphere, MRI machines, credit card magnetic strips, and compass navigation. Groups rotate, annotate with sticky notes, and identify which field property each application relies on.

How does a compass work differently at the equator versus the poles?

Facilitation Tip

While students prepare their Gallery Walk posters, ask them to include a specific example of how magnetic fields transfer energy in their chosen application.

What to look for

Pose the question: 'If you cut a bar magnet in half, what would you find at the cut surfaces?' Facilitate a discussion where students explain their reasoning based on the concept of magnetic poles always coming in pairs.

• Understand
• Apply
• Analyze
• Create
• Relationship Skills
• Social Awareness

Activity 04

• Jigsaw
• 30 min · Small Groups

Jigsaw: Why Magnetic Monopoles Do Not Exist

Groups research why breaking a magnet in half always creates two new magnets, present findings to the class, and discuss whether magnetic monopoles are theoretically possible. This connects to the idea that magnetic field lines always form closed loops.

How does the Earth's magnetic field protect us from solar radiation?

Facilitation Tip

For the Jigsaw activity, assign each expert group a different magnet type and have them prepare a short script explaining why monopoles cannot exist in their case.

What to look for

Provide students with two bar magnets. Ask them to predict and then demonstrate how the magnets will interact when brought together in different orientations (e.g., north to north, north to south). Have them draw the setup and label the poles involved.

• Understand
• Analyze
• Evaluate
• Relationship Skills
• Self-Management

A few notes on teaching this unit

Start with the Think-Pair-Share to surface prior knowledge and expose misconceptions early. Use the Mapping Magnetic Fields lab as the anchor activity because it provides concrete evidence to challenge abstract ideas. Close with the Jigsaw to reinforce the concept that poles always come in pairs, which is foundational for later electromagnetic topics. Avoid rushing to the conclusion that field lines show particle paths; instead, let students discover through mapping that lines indicate force direction only.

Successful learning looks like students confidently drawing field lines, labeling poles correctly, and explaining why field strength is greatest at the poles. They should also be able to connect their lab observations to real-world applications and articulate why monopoles do not exist.

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Watch Out for These Misconceptions

• During the Lab Investigation, watch for students who claim the compass points to the geographic North Pole because Earth’s north pole is magnetic.

  During the Lab Investigation, have students trace the field lines from a bar magnet and compare them to Earth’s magnetic field lines drawn on a printed map, asking them to label the poles on both and explain why the compass aligns as it does.

• During the Jigsaw, watch for students who believe some magnets may have only a north or south pole.

  During the Jigsaw, provide each group with a small ceramic magnet and safe nippers, then ask them to break the magnet and observe the new poles that form, using this to revise their explanations.

• During the Think-Pair-Share, watch for students who interpret magnetic field lines as paths particles would follow.

  During the Think-Pair-Share, ask students to draw a proton’s trajectory near a bar magnet and compare it to the field lines they drew earlier, prompting them to notice that the path curves but does not follow a single line.

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Methods used in this brief

• Think-Pair-Share
• Gallery Walk
• Jigsaw