TOYBOX
Heather Brasell, Coffee High School, 1303 S Peterson Ave, Douglas 31533.
Ginger Tarver, Westside Elementary & Ken Suttles, Coffee Middle School.
Presented at the Annual Meeting of GSTA, Savannah. February 1994.
MATTER
Postal scales. Pivot type illustrates torque and levers. [$3.75 Science & Surplus] They measure mass. Spring
types show elastic potential energy. Their displacement is proportional to the force (weight) exerted on them.
Wave-in-a-bottle demonstrates immiscible fluids. It is also a fun way to learn about surface behavior. Make
your own from turpentine, water and food coloring.
Underwater-wheel demonstrates immiscible fluids and also torque and angular momentum. [Keychain $2
Oriental]
Soluble paper (also soluble starch packing peanuts) are a fun way to learn about solubility. [Melting money $4
Flinn]
Superabsorbent polymer, sodium polyacrylate, is used in diapers. It absorbs over 800 times its weight in water
instantly. It can also be used to learn about polymer chemistry and osmotic pressure. [$8/100 g Flinn]
Grow creatures are 4" animal shapes made from superabsorbent sodium polyacrylate material mixed with
glycerin. Place them in water and they will grow by a factor of up to 6 times. The process is reversible. Dry
them out and notice that they dry fastest from the most pointed parts first. [$2.45 Flinn]
Smart and stupid balls demonstrate differences in elasticity. One ball will bounce very high; the other looks the
same but will not bounce. The properties of the stupid (no-bounce) ball, low resiliency and good energy
absorber, make it useful as a shock absorber. They are also fun to use to learn about energy and polymer
chemistry. [$4.20 Flinn]
Wall walkers demonstrate physical properties and balanced and unbalanced forces. Throw one against a smooth,
clean surface, and it will stick. After a while, it will slowly release and flip end-over-end down the wall. They
are made of a variety of plastics. [Oriental Trading]
Magic tree demonstrates crystal growth within a class period. Buds form in about 15 minutes. The tree consists
of blotting paper cut into the shape of a Christmas tree placed into a solution (e.g. 6 tblsp NaCl, 1 tblsp
ammonia, 6 tblsp water and 6 tblsp liquid laundry). The solution moves up the tree by capillary action. Crystals
from by evaporation which is most rapid at the pointed branch tips. [$1.50 Flinn] Magic rocks also demonstrate
growth of a variety of crystals. [$4 Flinn]
Mystic sand demonstrates interesting behavior of sand coated with a hydrophobic material. It can make
underwater columns, towers and interesting designs. Its water repellent particles stay together as a separate
phase in water, similar to the phase separation between oil and vinegar. The original invention was used to
remove oily contaminants from water systems. [$5.50 Flinn]
Foam brick useful in demonstrating density. I also use pumice. [Science & Surplus]
Magic milk tumbler is a discrepant event that is useful to get students thinking about conservation of volume.
Imp bottle [$1.50 Toys R Us], wire balancing ornaments [$9/doz Oriental], and Radical Blocks are useful in
demonstrating center of mass.
Disappearing ink demonstrates the use of indicators and the effect of changes in pH. It is a bright blue waterbased solution which disappears within minutes leaving only a colorless water spot that evaporates slowly,
leaving a small amount of white residue. It is thymolphthalein dissolved in ethanol and diluted with water. It has
NaOH added to a final pH of 10-11. Make your own using phenolphthalein, the active ingredient in Ex-Lax.
___________________________________________________________________________
FORCE, MOTION AND MACHINES
Etch-a-sketch demonstrates the concepts of vectors. Lines on the sketch board are produced by controlling two
separate knobs, one controlling the up-down length, the other controlling the left-right length. This is analogous
to the concept that any vector can be resolved into x and y components at right angles to each other. [Walmart]
Glide balls. Useful for demonstrating Newton's first law of inertia. TPT, 30, Dec. 1992. [$12/doz Oriental]
Newton's balls [Edmund], Newton's clackers [Oriental], or Bumper balls [$4.75 Edmund]. These demonstrate
Newton's third law (action and reaction), conservation of momentum in an elastic collision.
Balloon racers. These demonstrate Newton's third law (action and reaction). [Oriental Trading]
Water rockets provide an enjoyable lab on Newton's laws, learning about the relationships between force and
motion. They can also demonstrate energy conversions. [Walmart] You can make your own from plastic soda
bottles.
Slinky, apart from demonstrating wave properties, are useful in demonstrating that the amount of stretch is
proportional to the force applied to it (Hooke's law). They can also be used to demonstrate simple harmonic
motion and conversion of energy from potential to kinetic and vice versa. They are included in the video Toys in
Space.
Centrifugal hoop [$6 Oriental] and Metallic spinner [$4.80/doz Oriental] are inexpensive devices to
demonstrate centrifugal effects. This can be used to explain how Earth is an oblate spheroid.
Centrifugal Christmas tree also demonstrates centrifugal effects. [$1.50 Stuckeys]
Tornado in a bottle. Swirling a water-filled bottle that has a hole in its cap causes a tornado-like whirlpool to
form in the bottle. The tornado does not persist in a sealed bottle. The draining water loses some angular
momentum as it leaves the bottle. This is transferred to the water remaining in the bottle, counteracting the loss
of angular momentum due to friction. For the draining water to maintain its angular momentum, as it
approached the narrow mouth where it has a lower moment of inertia, the water would have to increase its
speed. This would mean increasing kinetic energy by more than it could gain from gravitational potential
energy. [$2 Edmund]
Celt or rattleback. These have a counterclockwise spin bias that results from the shape of the smooth ellipsoidal
botton and the distribution of the mass with respect to the axis of spin. This causes coupled oscillations between
rocking motion and rotation. The long axis of the ellipsoid is aligned at an angle of from 5-10 degrees to the
long axis of the flat top. Just before reversing direction, the rattleback rocks up and down on its long axis.
History: Rattlerocks were discovered by archaeologists studying prehistoric adzes and axes called celts. They
were found along river banks where the action of the water smoothed them into their ellipsoidal shape. [Edmund
$2] Amateur Scientist column, Scientific American, Oct. 1979.
Tops. History: The top dates back to the beginning of recorded history, shown in art dating back to 500 B.C.
with Greeks, Asians, Indians, Africans and Europeans. It is found in almost every civilization around the globe,
made from a wide variety of materials. Science: Newton's first law says that moving objects continue in the
same direction until acted on by another force like friction or gravity. When you spin the top, the energy is
stored by the disc as inertia. Friction on the tip and gravity try to tip over the top, but these forces are resisted by
inertia. When the top is tipped at an angle, gravity tries to pull it over and the top precesses. The handle moves
as it travels in circles and rotates on its axis and tries to stand upright. As it slows down, there is no longer
enough stored inertia to resist gravity and the top precesses wildly until it falls over. "Snoopy" top was
demonstrated in Toys in Space video. I have students overlay patterns on the top of the disc to investigate
optical illusions such as color mixing, Benham's disk, and depth spinner. [$3/gross Oriental]
Gyroscope was demonstrated in Toys in Space video. [$5 Flinn]
Pendumonium is a chaotic pendulum made from a cellection of interchangeable parts that can be linked in
different ways. [$13 Edmund]
Koosh shows flattening of a spinning object, similar to galactic disks. TPT, 'Oct 1989
Mousetrap is a great demonstration of a combination of simple machines and energy conversions.
Dragonfly demonstration of lift (Bernoulli principle) [$3.60/doz Oriental]
Forces in fluids can be seen with Hero's fountain, Cartesian divers, and games like Claws.
___________________________________________________________________________
ENERGY
Jumping disc. This demonstrates energy conversions and the principle of differential expansion. The disc is
made from two thermostatic metals bonded together. Warm to 72-78 degrees F. Rub the silver side of the disk
to heat it. Press down on the silver side until it clicks into position. Place it face-up on a cold surface and stand
back. The disc will jump into the air. [Edmund] Alternative: cut a disc out of racquetball. This can be used to
demonstrate elastic potential energy. Science Scope, Nov./Dec. 1991.
Spring-loaded suction toy. I use this to demonstrate energy conversions and to recycle through other science
concepts: Work to compress the spring, Hooke's law, weight of air presses rubber cup against table top, elastic
potential energy of compressed spring changes to kinetic energy as toy pops up, work done by spring in
restoring itself to original length, impulse exerted by spring on table, reaction force of table top causes change in
linear momentum, internal friction of spring dissipates some of the stored potential energy, etc. TPT Mar. 1990.
Energy conversions can be demonstrated by a variety of toys:
Perpetuo [$8.25 Edmund]
Yo-yo was demonstrated in Toys in Space video.
Chinese yo-yo [Oriental Trading]
Wind-up toys (also shown on video Toys in space)
Flywheel cars also demonstrate gears (simple machines)
Spring-powered dart gun (also demonstrate projectile motion)
Trick hammer demonstrates electrical to sound.
Jack-in-box [$1.50 Oriental]
Flash rocks [$2.50 Science & Surplus]
Light sticks demonstrate the conversion of chemical energy to light (chemiluminescence). This reaction is
similar to the one used in glow worms, fireflies and phosphorescent bacteria.
Two-potato clock demonstrates the conversion of chemical potential energy to electrical energy. It runs for
weeks on a variety of chemicals including soft drinks. [$20 Edmund]
Sterno (canned heat) demonstrates the conversion of chemical energy to light and heat. It is also a good
demonstration of a colloidal substance. The gel burns, leaving a residue of calcium carbonate. Make your own
with 3 g calcium acetate, 10 ml water (stir to dissolve most of the salt), 75 ml ethanol. A pinch of salt makes the
flame more visible. Flinn ChemFax 193.00.
Radiometer demonstrates the conversion of heat (infra-red radiation) to mechanical energy. Vanes, black on one
side and white on the other, are balanced on a low friction bearing. Set it in bright light or sunshine and the
vanes spin. This also demonstrates how the black surface absorbs more heat energy than the white surface. [$10
Flinn]
Piezoelectric lighters demonstrate the conversion of mechanical energy to electrical energy. The barium titanate
crystal is tetrahedral. When the crystal is deformed by pressure, it becomes electrically polarized. In commercial
lighters, the charge separation produces a spark that ignites the fuel. TPT Nov. 1991.
Snap-n-pops, a relatively safe explosive noisemaker, demonstrates the conversion of chemical to sound energy.
It is made of light paper loaded with coarse sand coated with silver fulminate (Ag2(CNO)2) When it is thrown
against the ground, friction sets off the chemical reaction with a quick bang, but little flame and almost no gas.
Blaster balls demonstrate the conversion of chemical to sound energy. They contain chemicals similar to the
caps used in cap guns. The two ceramic balls are both coated with a thin layer of a mixture of potassium
chlorate, sulfur, glue and powdered glass. When either ball hits a substance containing lots of silica (e.g.
concrete or the other ball), the silica produces enough friction and heat to detonate the mixture and make a caplike blast. [$2 Science & Surplus]
___________________________________________________________________________
HEAT
Heat Solution provides an excellent demonstration that freezing is a heating process. This is a supercooled,
supersaturated solution of sodium acetate trihydrate and a stainless steel disc in a sealed vinyl pouch. When the
metal disc is bent, it causes a single molecule of solution to crystalize and act as a seed crystal. This starts a
chain reaction which causes the entire solution to crystallize. As it crystallizes, the temperature of the solution
climbs to the freezing point which is 58 oC (136 oF). The process is exothermic. It will remain hot for about 30
minutes.
NaC2H3O2 (l) + 3 H2O <--> NaC2H3O2.3H2O (s) + 19.7 KJ/mole
Some models can be heated to melt the crystals and reused 30-40 times. Sold as REheater (Frey), Hothands, etc.
[Walmart $4]
Drinking bird and hand boiler
Shrinky Dinks. These can be used to demonstrate ratios and investigate density. Shrinky dinks are sold as sheets
of clear plastic, usually with pictures of cartoon characters etc. printed on them. Cut out and color the shapes
and heat them at 163 oC (325 o)F. Within four minutes, the shape will shrink to about one third of its size with
all dimensions in the same ratio as the unshrunk piece, but it will be nine times thicker. The material is a
bioriented polystyrene film that has been extruded under stress. Upon heating it exhibits "memory effect,"
softening and shrinking to its original pre-stressed size. Some commercial products (soda bottles, lids for delistyle containers) demonstrate the same behavior. [$6.25 Flinn]
Nitinol. ChemMatters [$1 Flinn] Flinn also sells a thermobile device consisting of a nitinol wire loop around
two pulleys, one brass and the other plastic. It generates power without a battery or motor. [$30 Flinn]
Liquid crystals are a viscous jelly-like organic compound in a transition state between solid and liquid forms.
They can indicate small temperature differences by changing color. They are sold commercially as space fidgets,
fickle foam, postcard thermometers, and aquarium thermometers. I also use them to demonstrate differential
rates of heat absorption by different colors. [$3-4]
___________________________________________________________________________
SOUND
Button-on-a-string. Demonstration of resonance and angular momentum. Notice the example of resonance as
you have to add energy at regular intervals. Notice the stable upright position attained by the button due to
angular momentum and gyroscopic action. Notice that angular acceleration is inversely proportional to
rotational inertia (button size). Explore the relationahip between resonance frequency and button size. TPT, Oct,
1989.
Chatterring. As the small rings spin they progress downward, getting energy from gravity to keep spinning.
Ultimately the player supplies the energy by rotating the larger ring to cancle the downward fall of the small
rings. This is related to the chattering that happens in machinery when a shaft is rotating in a badly worn
bearing. Thie process is similar to the hula hoop. For continuous spinning, the ratio of diameters of hole to rod
should be 1.4 to 2.3. The greater that ratio, the greater the downward spin. TPT, 30, May, 1992.
Gee-haw whimmy diddle demonstrates resonance.
Demonstrate interesting sound effects with
Zube tube
Groan tube [$1 Novelty stores]
Whirly tube
Bullroarer Make your own from a paint stirrer.
___________________________________________________________________________
LIGHT AND COLOR
Rainbow glasses. Diffraction grating film splits light into its spectrum. [Flinn $1.35]
Holograms
Laser dazer is a rotating disk with patterns on its surface. Reflected light shows diffraction patterns. [$6 Flinn]
Fibre optics sold as attachments to flashlights and ornaments. Also sold to light gun barrels.
Signalling mirrors demonstrate uses of reflected light. [Military surplus]
Kaleidoscopes and Periscopes link with patterns of reflections in multiple mirrors. Make your own very simply.
Mystery bank demonstrates reflection. Drop coins into the money bank and they seem to disappear.
Fly-eye prism viewer produces multiple images.
Ulexite (TV stone) is a mineral that demonstrates behavior similar to fiber optics.
Calcite is a mineral with crystal shape that produces double images by reflection off the different faces of the
crystal.
Fresnel lens demonstrates that refraction takes place only at the surface boundary.
Moire box demonstrates how four pigments (magenta, cyan, yellow and black) are combined in printing to
produce colored pictures. Other transparencies have moire patterns that can be combined to show interference
patterns analogous to electric field lines and two-point wave interference (nodal and antinodal lines).
___________________________________________________________________________
ELECTRICITY AND MAGNETISM
Plasma ball demonstrates the fourth state of matter. Gases subject to extremely high voltages (as provided in
lightning, electrostatic generators, Tesla coils) exist as plasma. When you touch the glass dome, the streams of
plasma are attracted to your fingers which provide an electrical ground. Make your own plasma ball from a
large, clear light bulb in an insulated holder. Touch the base with a Tesla coil. TPT Oct' 1992.
Lazy Bones is a motorized carrier that starts when an object is placed on it and stops when it gets to the edge of
a table. It demonstrates open and closed circuits.
Magic light bulb contains a hidden dry cell. When you hold it in your hand, electricity flows through your hand
to complete the circuit and the light glows. This demonstrates that human flesh is a good conductor of
electricity. Other versions of this are the Energy ball and Singing bear.
Balafire light bulb has an incandescent carbon filament that vibrates violently back and forth, creating a visually
unusual effect. A permanent magnet in the base subjects the filament to a force that alternates 60 times a second.
Crdl and Magnasticks [$25 Edmund] consists of a strongly magnetized metal base and pieces of steel that are
attracted to the magnet. This is a good demonstration of induced magnetism.
Magnetic wheelo. Shown in the Toys in Space video. By slinging the wheel sideways in a circular arc to start
the wheelo using a combination of inertia and centripetal force. In conserving momentum the wheel will
continue moving along the track after the track is released. it will continue spinning to conserve angular
momentum. It transfers some of its angular momentum to the track as the track begins to turn.
Woolie Willie and Magnetic drop are magnetic games.
Magnetic dancer is a magnetic toy.
Magnetic marbles are fun to play with while you learn about collision theory. They are also useful to include in
a mystery box. These were used in the video Toys in Space.
Floating magnets
Neodymium supermagnets are made of about 70% iron, 5% boron and 25% neodymium and are magnetized by
an extremely powerful electromagnetic field. They demonstrate vividly a variety of concepts about magnetism.
The ink in the US paper money contains iron that is attracted to the magnet. When a magnet is dropped down a
copper tube, the falling magnet induces in the copper an electric current that has its own magnetic field
opposing the direction that the magnet moves. The magnet falls very slowly.
___________________________________________________________________________
SOURCES OF IDEAS
References
D. Katz. 1990. Chemistry in the toy store. (20 pp.) Dept. Chemistry, Community College of Philadelphia, 1700
Spring Garden Street, Philadelphia, PA 19130.
Teaching Science With Toys, CESI Sourcebook VI. ERIC/CSMEE, 1929 Kenny Rd, Columbus, OH 432105986. (614) 292-6717. [$16.50]
Wigginton, E. (ed.), Foxfire 6, Doubleday: New York. [Includes 100 toys and games.]
Suppliers
American Science and Surplus, 3605 Howard St, Skokie, IL 60076
(708) 982-0870
Anatomical Chart Co, 8221 Kimball, Skokie, IL 60076
(800) 231-6000
Edmund Scientific Co, 101 E. Gloucester Pike, Barrington, NJ 08007-1380
(609) 573-6260 (Service) (609) 547-8880 (Order)
Exploratorium Store, 3601 Lyon Street, San Francisco, CA 94123
(800) 359-9899
Flinn Scientific Inc., P.O. Box 219, Batavia, IL 60510
(708) 879-6900
Johnson Smith Co, P.O. Box 25500, Bradenton, FL 34206-5500
(813) 747-2356
Museum Products Co, 84 Rte 27, Mystic, CT 06355
(800) 395-5400
Oriental Trading Co, PO Box 2308, Omaha, NE 68103-0407
(800) 228-2269
U.S. Toy Co, 1227 East 119th St, Grandview, MO 64030-1117
(816) 761-5900