Magnets are one of the most versatile tools in a science classroom. They’re cheap, reusable, and help teach physics, engineering, and materials science all with the same handful of supplies. Below are three quick STEM lessons with magnets for middle and high school, each doable as a 15-20 minute classroom demo, a bell-ringer/filler activity, or a full homeschool science session. All three use small, lower-power magnets and are designed with older students in mind. Always supervise students closely when using magnets, and see the safety note at the end before you start.

1. Magnetic Force & the Inverse-Square Law (Physics + Data Analysis)

Concept: Magnetic force doesn't fade in a straight line as distance increases — it drops off sharply, following a pattern similar to gravity and electric force. This lesson lets students collect real data and see that relationship for themselves instead of just reading about it.

Materials: One 1/2" ceramic disc magnet per group, a steel washer or paperclip, a stack of index cards (or a ruler and a luggage/spring scale for a more advanced version), and graph paper or a spreadsheet.

Procedure:

  1. Place the magnet on top of a single index card, with the washer directly beneath.
  2. Add index cards one at a time, testing after each card whether the magnet can still hold the washer through the stack.
  3. Record the number of cards (a rough proxy for distance) at which the connection fails.
  4. Run several trials, then graph "distance" against "held/not held," or — for a more advanced version — use a spring scale to measure actual pull force in ounces at set distances and graph force vs. distance directly.

Discussion: Ask students why the drop-off isn't linear. This is a natural bridge to Newton's law of gravitation and Coulomb's law, both of which follow the same inverse-square pattern. 

2. Magnetic Levitation Engineering Challenge (Engineering Design)

Concept: Students build a small stack of "floating" ring magnets and engineer it for maximum stability (the same core principle behind maglev trains and frictionless bearings).

Materials: A 1/2" x 3/8" x 1/8" ring magnet 10-pack per group, a wooden dowel or thick pencil to thread them on, and a small block of wood or clay for a base.

Procedure:

  1. Thread three or four ring magnets onto the dowel, flipping every other one so that the poles face each other and repel instead of attract.
  2. Students will see the magnets settle into a floating stack, each one hovering above the last with a small gap.
  3. Challenge teams to engineer the most stable stack: Can they add a paper spacer or small washer between rings to change the gap? What happens if a ring is flipped the wrong way?

Discussion: Connect the demo to real maglev train technology and magnetic bearings, both of which use repelling magnetic fields to eliminate friction. Ask students to explain, in their own words, why the stack is stable in the vertical direction but easily tips over sideways — a great entry point into discussing equilibrium and restoring forces.

3. Magnetic Sorting & Materials Science (Real-World Engineering)

Concept: Not all metals are magnetic — and that fact is the basis of a multi-billion dollar recycling industry. In this activity, students sort a mixed pile of materials and discover which "rules" apply.

Materials: A magnet (the ceramic disc from Lesson 1 works fine), and a mixed pile of household items: steel screws or washers, aluminum foil or a soda can, copper wire, a few coins, a plastic bottle cap, and anything else on hand.

Procedure:

  1. Have students predict which items the magnet will pick up before testing anything.
  2. Test each item and sort into "magnetic" and "not magnetic" piles.
  3. Reveal the results: steel is magnetic, but aluminum, copper, brass, and most coins are not — even though they're all metals.

Discussion: This is the same principle industrial recycling facilities use to separate steel from aluminum on a conveyor belt at massive scale, and it's why aluminum cans need a separate sorting step (like eddy current separation) instead of a simple magnet. It's a natural jumping-off point for a broader conversation about materials science, recycling, and environmental engineering.

FAQ

What age group are these lessons designed for? Middle and high school (roughly grades 6-12). Magnetism lessons for younger students typically use much weaker ceramic or classroom magnets under close supervision — the neodymium magnets used here, while still low-power, are strong enough that they aren't appropriate for elementary-aged children.

How long does each activity take? Each one can run as a quick 15-20 minute demo or filler activity, or be expanded into a full class period with data write-ups, group presentations, or a design-challenge rubric for Lesson 2.

Do I need special safety equipment? No special equipment, but adult supervision is required throughout. Keep magnets away from students' fingers pinching between two attracting pieces, away from anyone with a pacemaker or other medical device, and away from credit cards, laptops, and other electronics that can be affected by strong magnetic fields.

Can these be adapted for a homeschool setting? Yes — all three use inexpensive, easy-to-find materials and work well as a single-student or small-group activity, no classroom required.

 

Looking for more classroom-ready magnet activities? Shop our full range of small, safe, and strong magnets for STEM lessons at ApexMagnets.com, or check out our Magnet Experiments page for more hands-on ideas.

Safety Warning: Magnets can be dangerous. Neodymium magnets, especially, must be handled with care to avoid personal injury and damage to the magnets. Fingers and other body parts can get severely pinched between two attracting magnets. Bones can be broken by larger magnets. These activities are designed for older students (middle school and up) and require adult supervision at all times — neodymium magnets are not safe for young children. Visit our Magnet Safety page to learn more.