Magnetic Explorer
What is Magnetic? Predict and then test!
Tubing
Holes for string
Topics: Magnetism
Materials List
 CD case (not slim),
media tray removed
 9 plastic push-on caps
from plastic bottles
(milk, juice, etc.)
 3 Straws, or glue
 Magnet (“pill” magnet,
~ 1 cm (3/8”) diameter
is recommended)
 (If pill magnet is used)
Tubing with an inside
diameter equal to the
magnet’s diameter, 3
cm (~1”) long
 Magnetic and nonmagnetic items, small
 Tape, clear
 Optional: string 40 cm
(16”) long
This activity can be used to
teach:
Next Generation Science
Standards:
 Properties of materials
(Grade 2, Physical
Science, 1-1, 1-2)
 Magnets and magnetic
interactions (Grade 3,
Physical Science, 2-3,
2-4, Middle School,
Physical Science, 2-3, 2-5)
 Science & Engineering
Practices (Grades K-6)
String tied through
slot near “D” tab
Pill magnet
This easy to assemble device allows students to investigate the magnetic
properties of many small items in a hands-on and safer fashion.
Assembly
1. Open the CD case and on the side that held the media tray place 9 upturned,
push-on, plastic bottle caps, or other caps having the same height.
2. Position the caps in a 3 x 3 pattern and check that the CD case can close.
The corner caps must be moved in, away from the top and bottom cover
“D” tabs. Secure caps in place with tape loops or glue. As an alternative
assembly, use straws as spacers as shown in the image above.
3. Open the CD case and fill the caps with magnetic and non-magnetic items.
For a list of suggested items, see the following page. A cap can be filled
with one type of item or mixed set.
4. Close the CD case and tape the 3 non-hinging sides. Thin items may slip out
of the caps if the CD case cover is not closed tightly
5. Almost any magnet can be used with the Magnetic Explorer. Some
magnets, such as ceramic magnets, will scratch the plastic cover of the CD
case. Covering or encasing the magnet will help prevent scratches.
6. Recommended - Insert a ~1 cm (3/8”) diameter magnet into a 3 cm (1”)
length of 3/8” tubing. Push the magnet in so that the magnet is slightly
indented into the tubing.
7. Optional - Tying the magnet to the CD case, as shown, will keep the magnet
handy. Thread the end of a ~ 40 cm (16”) long string through the slot as
shown and out the gap in the top cover. Secure with several knots. Secure
the string to the tubing. Placing a drop of glue on the knots will ensure the
knots will not unravel.
To Do and Notice
1. Have students predict which items they think will be attracted to the
magnet.
2. Have students use the magnet to test their predictions.
3. Have students talk about what surprised them and what they learned.
4. Students could suggest other items that could be put in the CD case.
Jewel Case design and idea sheet by Michael Pollock; illustrations by Jay Gluckman (RAFT)
Copyright 2015, RAFT
Science behind the Activity
We commonly label materials as being either non-magnetic, magnetic, or magnets. However all matter really is
magnetic, even if only at the atomic or sub-atomic level. This is true because all matter contains moving particles
(electrons, protons) that have charges (negative [-] or positive [+]). When a charged particle moves, a magnetic field
surrounding the particle is created. In an atom or molecule the individual magnetic fields, of each charged particle, are
usually oriented in random (different) directions so there is no (or almost no) overall magnetic field. Since most
elements are, at best, only very, very weakly magnetic, we considered them to be non-magnetic.
Magnetic materials include iron, nickel, cobalt, and many of the alloys made from them; such as the iron alloy we call
steel. The “weirdness” of sub-atomic magnetism can show up in items containing these elements. Each magnetic
material has many microscopic areas called domains. The atoms in a single domain have their magnetic fields
oriented in the same direction. The magnetic field of each individual domain will be pointing in a random direction,
so the material, overall, does not act like a magnet. When a magnet is brought near magnetic material the magnet
causes the random magnetic orientations of the domains in the magnetic material to “line up” in one direction. The
magnetic material will become a (temporary) magnet. The domains’ new magnetic orientation is such that the
opposite poles of the permanent and temporary magnet are closer than the like (same) poles. The attractive force is
thus stronger than the repelling force. The magnetic fields of the temporary magnet’s domains can become unaligned
again. This happens quickly for most materials and more slowly for others.
The attraction between a magnet and magnetic material will become stronger as the distance between them becomes
smaller.
Selecting magnetic and nonmagnetic items that look alike will help correct student misconceptions that all metal is
attracted to a magnet or that all brass colored items are not. If items from each list are mixed together in one section,
then the magnet can be used to separate them. This is similar to a process used in separating recyclable material.
Possible items to include
Will be attracted to a magnet
Will not be attracted to a magnet
Washers made of steel
Twist ties with a wire inside, cut into pieces, bent into “V” shape
Nails or brads made of steel
Coins that have a steel core (some English and other foreign coins)
Iron/steel wire sections
Nickel (some Canadian coins have a very high nickel content)
Mini sized paperclips (#0) [regular (#1) are too large for the caps]
Items that have an iron/steel core but are plated with a
nonmagnetic metal such as brass
Staples, groups of 3-6 broken off from a refill strip, (single staples
may slip out of a cap)
Screws made of steel
Chain (light fixture pull chain, etc.)
Steel item wrapped in aluminum foil as a “Why is that magnetic?”
puzzle.
Paper, cardboard
Cloth
Rubber band, balloon
Penny and other US coins (not a US nickel*)
Plastic straw, beads, wraps, etc.
Copper wire
Flat glass marble
Aluminum foil, washers, wire, coin
Wood pieces (craft sticks, toothpicks)
Brass (solid) wire, washers, brads
String, yarn
Items made of stainless steel are much less
attracted to a magnet than regular steel, some
are even nonmagnetic
*A US nickel has too little nickel to have an attraction, upward, greater than the attraction, downward, from gravity.
Using a US nickel may create the false idea that nickel is a non-magnetic material.
Web Resources (Visit www.raft.net/raft-idea?isid=202 for more resources!)


For more information on magnets - http://www.raft.net/ideas/Mini Magnet Wands.pdf
Information about magnetism and how magnets are used – http://my.execpc.com/~rhoadley/magwhy.htm
Magnetic Explorer, page 2
Copyright 2015, RAFT