Table of Contents
28. Musical Instruments (Straw Whistle)
29. Conductors
30. Electromagnets
31. Electrolysis
32. Secret Circuits
33. Buoyancy (different objects)
34. Color of Sun (adding colors to give white)
35. Repulsion of Like Charges
36. Lemon Battery Experiment
37. Blow up a Balloon with baking soda and vinegar
38. Make your own light bulb
39. Black Magic (colors)
40. The stick-o-meter (sticking force)
41. 2 point discrimination test (bio)
42. Inside-out-Bag (Air pressure)
43. Spider Gliders
44. Cloud in a Bottle
45. The human vacuum cleaner (Air Pressure)
46. Making a Compass
47. Milky Magic
48. Making a Circuit
49. Where does a Magnet work?
50. Alka-Seltzer Rockets
51. Powerful Push-Up (air pressure)
52. Dancing Coin
53. Head Harp (sound)
54. Magnets through Air, Liquid and Solids
55. Airplane without wings
56. The fly ball game
57. Making Waves
58. Magnets and Metals
59. Balance
60. Jumping Rice (electrostatics)
Amanda
Dunn
28. Physics of Music
This experiment is composed of three different experiments where each shows how to achieve different pitches. The first experiment is called “Good Vibrations”. It illustrates that object made longer vibrate slowly and makes a sound of a lower pitch. The second experiment is called “Pluck-A-Cup Strummer”. This challenges students to discover ranges of pitch that can be played by plucking a rubber band attached to a paper cup. The length of the rubber band affects the pitch. Holding the rubber band at different points along the length will produce lower pitched sounds with greater lengths and higher pitched sounds with shorter length. Length had a much greater impact on pitch than does degree of stretch. The third experiment is called “straw whistle symphony!” This illustrates the relationship between length of a vibrating object and its pitch. Students will see that a very small change in the length of the straw changes the pitch of the straw. Below are directions on how to complete each individual experiment.
The needed materials for “Good Vibrations!” are a flexible ruler and a table. The first step is to extend most of a ruler over the edge of a table, pressing the other end against the table with the palm of your hand. Lightly thump the extended end and listen carefully to the sound the vibrating ruler makes. The second step is to thump the end of the ruler lightly again, but this time watch the ruler to see how fast it is vibrating. The third step is to thumb the ruler harder. Will it vibrate faster or will the vibrations just be larger? Does the sound change? The fourth step is to thumb the ruler with only a small length extended over the edge of the table. The last step is to see how many sounds you can make with the ruler. Change the length of the ruler and the strength of the thumbs and see what happens?
The needed materials for “Straw Whistle Symphony!” are straws and scissors. The students should wash their hands before starting this experiment. Flatten one end of a straw by biting down on it and then pulling it between their closed teeth. Cut the flattened end into a point. Place the pointed end of the straw whistle in your mouth, press down gently with your lips, and blow. Practice will be needed to get the whistle to work. Next cut about ¼ of the straw from the unflattened end and play it. How does the whistle sound? Then make a new straw whistle. Have a partner cut the straw while one person it playing it. How does it sound? Now experiment and see what the students come up with their own experiments.
The materials need for “Pluck-A-Cup Strummer” are a disposable plastic or paper cup, long rubber bands, tape, and a sharpened pencil. The first step is to cut the rubber band to make it a single long rubber string. It should be at least 15 cm unstretched. If not you make need to tie two or more rubber bands together. The second step is to use a sharp pencil to poke a very small hole in the center of the bottom of the cup. Tie a knot in one end of your rubber string, then run the string through the hole in the bottom of the cup. Place a piece of tape across the knot inside the cup. Fourth is to hold the cup up to one ear and gently pluck the rubber string. The final step is to discover how many differently pitched sounds you can produce with the Pluck-A-Cup Strummer. Try holding the rubber band closer and farther from the cup to change the pitch. What else could be changed to make different pitches?
These three experiments will give the children their own chance to experiment by themselves. These experiments are inexpensive, fun, and easy to do. Enjoy!
29. Conductors
Kassi Pierce
Purpose: To determine if all materials conduct electricity.
Materials:
·Spring type clothes pin
·1 D-cell battery
·Aluminum foil
·Flashlight bulb
·Masking tape
·Testing materials: rubber band, paper, penny, nickel, dime, quarter
Procedure:
·Cut a rectangle of aluminum foil, 24in. X 12in.
·Fold the aluminum piece in half lengthwise five times to form a thin strip 24in. long.
·Cut the aluminum strip in half to form two 12in. strips
·Tape one end of each of the metal strips to the ends of the battery.
·Wrap the free end of one of the metal strips around the base of the flash light bulb. Hold the strip in place
with the clothespin.
·Test the electrical conductivity of the materials collected by touching the metal tip on the bottom of the
flashlight bulb to one side of the material while touching the free end of the metal strip to the opposite side
of the same material.
Write down your observations of each testing material.
1.Rubber band:_______________________________________________________
2.Paper:_____________________________________________________________
3.Penny:_____________________________________________________________
4.Nickel:____________________________________________________________
5.Dime:______________________________________________________________
6.Quarter:___________________________________________________________
Results:The coins were the only materials that caused the bulb to glow.
Why? An electric circuit is the path through which electrons move. A switch is a material that acts as a
bridge or pathway for the electrons. When the switch is closed, the electrons move freely, but when it is
open, the electrons stop. The only materials tested that allowed electrons to flow through them were those
made of metal. Touching the paper clip to one side allowed the electrons to flow out of the negative part of
the battery through the aluminum tape (conductor) into the bulb. The electrons continue their path from the
bulb through the aluminum strip and back into the positive end of the battery. As long as there is no break in
the system, the electrons continue to flow and the bulb will continue to glow.
Giselle DeGuia
30. Electromagnets
What is a magnet?
A magnet is an object that is
made up of materials that attract (pull toward) anything made of iron or
steel. This type of magnet is
permanent. It always works.
Show a permanent magnet.
What is an electromagnet?
An electromagnet is a
temporary magnet that only works when there is current flowing through its
coil. When the magnet loses its
magnetic field it does not attract anymore.
Show an temporary magnet or
electromagnet.
How does it work?
A magnetic field around a
wire is circular and perpendicular to the wire. To make the wire’s magnetic field stronger and add to it, we can
coil the wire. Like shown:
One loop's magnetic field
Now let’s try and make our own
ELECTROMAGNETS !
Supplies needed for electromagnet:
1.5 v battery,
long thin screw, electric tape and thin copper wire (insulated or not) (about
20 in. depending on how strong you want the electromagnet)
These can all be
found at your local hardware store.
-Take the 20 in.
wire and wrap it as tight as possible around the screw leaving about 2 in.
strand on each side. Make sure the wire is coiled close together and is
touching the screw.
-Tape one end of the wire to
the bottom of the battery making sure that the wire goes right through the
center of the bottom of the battery. Do
the same with the other end of the wire to the top of the battery also making
the wire go through the center of the top of the battery.
-Hints:
*Hold the battery where the
label is and NOT where the wire was taped.
The wire and screw can get very Hot.
*The more coils around the
screw the stronger the magnet.
(
More coils means more magnetic field which leads to a stronger magnet)
Now
that everyone has made their magnets, See whose electromagnet is the strongest
by letting the screw part of the electromagnet roll around in a pile of paper
clips. Whoever has the most paperclips
connected to the screw in one lift wins!
31. ~ ~ ~ ~ ~ Splitting Water ~ ~ ~ ~ ~
Michele Pena
Subject: Science
Grade Level: 3 – 5
Teaching
Strategy: Small groups
Objective: To illustrate for students that not only is electricity used to power machines, it can be used to produce chemical changes.
Materials provided:
· Plastic cup
· 1 tsp. Salt
· Popsicle stick
· 2 pencils
· 3 x 5 card
· 9 Volt battery with electrical wires
Procedure:
Step 1. Obtain warm water from restroom filling plastic cup 2/3 full.
Step 2. Pour salt into water and mix with Popsicle stick, let stand.
Note: Electrolysis is the process in which electric current passes through a substance causing a chemical change, usually the gaining or losing of electrons. Can you predict what will occur when a current is introduced into a cup of water?________________________________________________________
Step 3. Using a pen, poke two holes about an inch apart in the center of the 3 x 5 card. Place the 2 sharpened pencils into these holes.
Step 4. Attach the 9 Volt battery to the holder and wires.
Step 5. Place the 3 x 5 card on top of the cup of water so that two pencil ends are submersed in the water.
Step 6. The pencil ends sticking up are acting as electrodes, touch one wire to each of the ends of the pencils. Observe what happens in the water.
What do you think is happening?___________________________________________
Hydrolysis is the chemical reaction in which water and another reactant exchange functional groups to form two products, hydrogen and oxygen.
Conclusion: We have used the chemical electricity of the battery to pass through and between the electrodes (the pencils) and split the water into hydrogen and oxygen, which collect as very tiny bubbles around each pencil tip.
32. Secret Circuits (4th grade and
up)
Jackie Romo
I. Purpose: A circuit is a “loop” for electricity to travel through. In this activity, students will learn about circuits and how they work.
II. Materials needed:
1 D size Battery
1 flashlight bulb
18-26 gauge copper wire (sold at home depot)
Masking tape
1 15X26 cm piece of cardboard
8 brass fasteners
Pen or pencil
1 marker for labeling
*Before making your circuit board, decide whether you, the teacher, want to make the circuit board for your students ahead of time or if you want your students to make the board themselves. If your students make the board, have them trade their circuit board with other groups or students in the class so that circuits stay a secret. The students should not know where the wires are located.
III. Procedure:
MAKING YOUR SECRET CIRCUIT BOARD
1. Cut out a 15X26cm piece of cardboard.
2. With a pen or pencil, poke 8 holes through the cardboard and label each hole 1-8. (this is the front side of your board.)
3. Push the brass fasteners through the holes and open the leaves of the fasteners to secure them.
4. Cut 3 pieces of wire about 6 cm long and attach each wire on the back side of the circuit board to any two brass fasteners. Make sure to connect the wire to the fasteners on the backside of the cardboard so that when you flip it over to the front side, all you can see are the labeled, brass fasteners; not the wires.
MAKING YOUR CIRCUIT TESTER
1. Cut two 25 cm long pieces of copper wire.
2. Take one wire and wrap one end of it around the metal base of the bulb and twist the wire closed. Secure the wire with tape but do not cover the bottom tip of the bulb.
3. Connect the other end of the of the wire to the positive end of the battery and secure it with tape.
4. Take the other copper wire and secure one end to the negative side of the battery.
IV. Activity
USING YOUR SECRET CIRCUIT TESTER
Students should now try to find where the 3 wires are hidden without flipping over the circuit board. In order to make a complete circuit and make the flashlight bulb light, the battery, wire, and bulb must make a complete circuit or loop, with at least one of the hidden wires.
To find the hidden wires, touch the free end of the wire from the battery to any brass fastener on the top of their circuit board. Then, touch the bottom tip of the bulb to any other fastener. If the bulb lights, then there must be one or more wire connecting the two brass fasteners. Have the students test their board until they are able to guess where all 3 wires are hidden.
Have the students draw their circuit board to record results.
V. Source: The Best of Wonder Science
33. Buoyancy
Elaine Galvery
Grade Level: 3
Purpose: To be made aware of the principles of buoyancy and
how we see or experience it in our every day lives.
Supplies: medium plastic containers, golf balls, ping-pong balls or empty plastic Easter egg shells, clay, pennies or hard candy pieces (Skittles), paper for flags, toothpicks or masts.
Instruction (optional): The teacher can tell the students about divers and what
they have to do to either stay afloat or dive. The following website, www.uncwil.edu/nurc/aquarius/lessons/buoyancy, gives good information about the Aquarius Sea Lab, scientific divers, and information for supportive instruction on buoyancy.
Activities:
- Students will fill their plastic containers about 2/3 full of water.
- Students will take their golf balls and decide if they will sink or float.
- Students will drop carefully the golf ball into the water. What happens?
- Students will now take the empty plastic Easter egg shells and decide if they will sink or float. They will carefully drop the egg into the water. What happens?
- Students will be asked to fill their egg with the candy and see how many pieces it takes before the egg starts to sink. You can make a contest out of this – who got the most candies inside the egg and it still floats.
- Students will now take some clay and make a ball out of it, about the same size as the golf ball. Will the clay ball sink or float?
- Since the clay ball did sink, instruct the students to shape the clay into a boat with greater surface area. They will probably experiment as to what shape this boat will be. Then have the students try to float their boat. There will most likely have to be modifications made on their boats for them to be successful.
- When they finally get their clay boats to float in the containers, give them a toothpick and some paper to make a mast and sail for their boat.
- Now ask the students to begin filling their boats with the hard candies. Again a contest can be done to see whose boat can hold the most candy and still float.
Conclusion: Students have had interactive activities that help them gain a better understanding of what buoyancy is. Archimedes Principle can be mentioned and be introduced to “displacement of water vs. an objects buoyant force.” Students have learned that weight and mass affect an objects ability to sink or float through the construction of their own clay boats.
34. Color of Sun
Breanna Bly
Purpose: To show that the sun has all the colors of the spectrum
Materials: Compass (or handout), crayons, scissors, glue and string.
Procedure:
1. Draw two six inch diameter circles.
2. Bisect the circles into six equal parts
3. Color each section a different color using red, green, yellow, blue, purple and orange.
4. Cut both circles out.
5. Glue both non colored sides together.
6. Punch two holes near the center of the circle.
7. Use a string or rubber band, and place it in one hole and out the other and tie the two ends of the
string together.
8. Place your index finger through the string on both sides, twist back and forth to see white light.
35. Repulsion of Like Charges
(Tammy Ritter)
Objective: To understand the concept behind "static" electricity and positive and negative charges.
Materials: String, cheerio cereal, comb, balloon, paper plate, salt and pepper, a piece of wool or felt.
Procedure: Review positive and negative signs and remind the kids that electrons move. Tie the string to a piece of cheerio cereal and have someone hold the string in the air or attach it to something so that it is free standing. Take the comb through your hair to gain an electric charge. Bring the comb toward the cheerio and watch it attract to the comb and then bounce off. (The cheerio is neutral and therefore attracted to the negatively charged comb. When they touch, the cheerio receives the negative charge and then repels the comb because they have the same charge.) Next, sprinkle some salt and pepper onto a paper plate. Stir it up. Ask someone to separate the salt and pepper for you. After a minute or so of trying offer some assistance. Blow up a balloon, rub wool or felt on the balloon. Bring the balloon one inch above the plate and watch the pepper jump from the plate onto the balloon.
Follow up: Discuss why the pepper is attracted to the balloon. (The balloon has a negative charge and the negative electrons in the pepper repel by going to the end of the pepper that is opposite that of the balloon leaving the positive protons to be on one the side of the pepper closest to the balloon.) Next you could let them do the experiment on their own.
36. Lemon Battery
Experiment
Valerie Walker
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For
today’s science experiment, it’s possible to make your own simple battery out
of materials you find around the house. You will need:
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Steps
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In this case, the zinc coating on the nail is the negative electrode and the copper wire is the positive electrode. The lemon juice, which is slightly acid, acts as the electrolyte. You have just created a battery cell!
You can use a voltmeter to measure the voltage of your cell. Touch the negative lead on the voltmeter to the nail and the positive lead to the wire. It should read nearly a half a volt. If you take the nail out and replace it with a paperclip you will see the reading on the voltmeter decrease. You can also connect several lemon batteries to measure the increasing voltage.
37. BLOW UP A BALLOON
WITHOUT WASTING A SINGLE BREATH
Tanya Lopez
Material: plastic (1liter) bottle
balloons
tissue paper(different colors)
1/2 C vinegar
1 T baking soda
Directions: Place a
tablespoon of baking soda onto the tissue. Roll the tissue into a tube
around the baking soda and twist closed the ends like a rolling pin. (2)
Pour the vinegar into the bottle - drop the baking soda into the bottle.
(3) Moving quickly, slip the neck of the balloon over the opening of the
bottle and hold it in place.
Objective: Action, reaction,
result - when the tissue paper tears and the baking soda and vinegar melt, a
reaction takes place, carbon dioxide, a gas is produced. The gas expands
out of the bottle and into the balloon - Blowing it up.
Key words for students:
Expand: to increase in size or volume.
Gas: a state of matter, such as air, that has no difinite shape, but
takes the shape
of the container it is in.
Nancy Keller
38. Make Your Own Light Bulb!
Supplies:
- 3 Fresh flashlight batteries (D cells, 1.5 volts)
- Metric ruler
- Tape
- 2 insulated copper wires (25 cm long)
- Nail
- 1 wire twist tie (from a plastic bag)
- Modeling clay
- Small glass jar (baby food jar)
Instructions:
1. Lay three batteries end-to-end. The positive ends of the batteries should all point in the same direction. You and your partner should tape the batteries together.
2. Mold some clay into a patty a little bigger around than the mouth of the jar. This will be the base of your light bulb. Poke your two wires up through the modeling clay base. The wires should stick out about 5 cm and be about 3 cm apart.
3. Peel off the paper or plastic from the twist tie so that only the bare wire remains. Wind the wire around the nail so that your wire is coiled like a spring. Leave a little bit of the wire straight at both ends. Take the wire off the nail. The wire is the filament for your light bulb.
4. Twist the ends of the copper wire around the ends of the filament to attach the filament to the wires. Do not let the coils of the filament touch each other. Turn the glass jar upside down over the wires and filament. Press the jar down into the clay. You light bulb is now ready to light!
5. Darken the room. Touch the ends of the wires to ends of your battery. One wire on one end of the battery and the other wire on the other end of the battery. Hold them on tightly. Watch the filament. What happens? The electrical energy in the batteries is converted into what other kind of energy?
6. Experiment
to make a better light bulb. You might
change the length, thickness, or kind of metal used for the filament or for the
connecting wires, or change the strength or number of batteries. What
kind of changes do you think will make the light bulb burn more brightly?
Be sure that:
1. You get off ALL the paper or plastic from your twist tie, it will smoke and burn when you light your light bulb.
2. The jar is in place before connecting the wires to the batteries.
3. The wires are disconnected before removing the jar.
4. Not to touch the wires after burning your light bulb, they are very hot.
39. Black Magic
Longina Burroughs
Objectives
- To find out what makes up the color
black.
What do I need?
·
Scissors
·
White coffee
filters
·
Black marker
(not permanent)
·
Water
·
Coffee cup or
sometime of cup
·
Clothespins
What do I do?
1-fold coffee filter in half and then
in half again creating somewhat of a triangle.
a. b.
c.
2-Fill cup with water.
3-Draw a black line about one inch
from the point and draw designs about it on both sides of the coffee filter.
4-Put the pointed side of the coffee
filter in the water. You just need to
put the tip in the water. Let the water soak all the way up the coffee filter.
5-Observe what is happening.
What’s Going
On?
Most
nonpermanent markers use inks that are made of colored pigments and water. On a
coffee filter, the water in the ink carries the pigment onto the paper. When
the ink dries, the pigment remains on the paper.
In this
experiment, you're using a technique called chromatography. The name comes from
the Greek words chroma and graph for "color writing." The technique
was developed in 1910 by Russian botanist Mikhail Tsvet. He used it for
separating the pigments that made up plant dyes.
There are
many different types of chromatography. In all of them, a gas or liquid (like
the water in your experiment) flows through a stationary substance (like your
coffee filter). Since different ingredients in a mixture are carried along at
different rates, they end up in different places. By examining where all the
ingredients ended up, scientists can figure out what was combined to make the
mixture.
Why does mixing many colors of
ink make black?
Ink and
paint get their colors by absorbing some of the colors in white light and
reflecting others. Green ink looks green because it reflects the green part of
white light and absorbs all the other colors. Red ink looks red because it
reflects red light and absorbs all the other colors. When you mix green, red,
blue, and yellow ink, each ink that you add absorbs more light. That leaves
less light to reflect to your eye. Since the mixture absorbs light of many
colors and reflects very little, you end up with black.
6-Open
up your coffee filter and allow it to dry.
After it is dry take your clothespin and make it into a butterfly but
gathering the middle and putting the clothespin around it.
Meg
Graber
40. The Stick-O-Meter
This is a fun activity to
do with kids from first to about forth grade.
Have the students work in partners for this activity. Kids know that their daily peanut butter and
jelly sandwiches are sticky but how sticky are they??? And how should they be kept to preserve that
stickiness?? Create a Stick-O-Meter to
find out.
Materials:
1 Large plastic or foam cup (32 oz.) Ruler
5 Foam cups (8 oz.) String
Peanut Butter Jelly
Aluminum Foil Pennies
Plastic Wrap Tape
Spoon Pencil
4 Small Paper Plates Honey
Paper Towels
- Cover your work space with paper towels (to
make clean up easier). Set the big
cup upside down on the paper towels and balance the ruler on top.
- Make a handle for one of the smaller cups by
taping the two ends of a piece of string and taping the ends to opposite
sides of the cup near the rim.
Make sure the handle is long enough so that the cup touches the table
when the handle is put over the balanced ruler.
- Make a shorter handle for another small cup,
and tape the string to the cup so that the cup will hang about 3 inches
off the table when the handle is over the balanced ruler.
- Now hang the two cups from opposite sides of
the hanging ruler and tape the string to the ruler and place one of the
paper plates under the cup with the long handle.
- Using a spoon smear a layer of jelly onto the
bottom of the long handled cup and push it onto the plate. Place a pencil on top of the big cup
under the center of the ruler.
- Have one partner hold down the paper plate
while the other begins to put pennies into the hanging cup, one at a
time. When the jelly cup pulls
away from the plate count the number of pennies in the cup and record the
number on the chart below
- Now cover the plate with the foil. Put the same amount of jelly on the cup
as before and stick it to the foil.
Repeat step 6.
- Now cover the plate with plastic wrap. Put the same amount of jelly on the cup
and stick it to the plastic wrap.
Repeat step 6.
- Repeat steps 2,5 and 6 with the honey.
- Now repeat steps 2, 5 and 6 with the peanut
butter.
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Number |
of
Pennies |
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Jelly |
Peanut Butter |
Honey |
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Paper Plate |
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Aluminum Foil |
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Plastic Wrap |
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- Compare the results of your testing to find
which sandwich is stickier, peanut butter and honey or peanut butter and
jelly.
- Would
it be better to take your sandwich to school wrapped in foil, plastic wrap
or paper?
Casandra Campbell
41. Science
Report
“2-Point Discrimination
Test”
Purpose:
For students to find out what areas of their bodies are most sensitive to touch? (ex. Hands, feet, thigh, forearm, etc.) To explore the difference in the degree of sensitivity the skin holds on different body parts.
Materials:
Toothpicks
Activity:
To find out what areas of the skin are more sensitive, have the students perform a 2-point discrimination exam of a friend. Give each pair of student’s two toothpicks. Make sure the tips of the toothpicks are not too sharp, if so press the points against a hard surface to create a more blunt end on the pick.
Have the pairs of students begin taking turns testing different areas on each other.
THE TEST:
While one student is performing the test, the other student should be closing their eyes so they cannot see where the toothpicks are. Make sure the students don’t press too hard! The student performing the test on a body part will begin by touching the toothpick tips on the skin several inches apart and slowly work the picks closer together. Make sure both tips touch the skin at the same time while moving them together. Have the student ask their partner if he or she felt 1 or 2 pressure points every time the picks move. If the student reported 1 point, spread the tips of the pick a bit further apart, and touch the previous point again. If the student reports 2 points have the partner open their eyes and see where their 2-Point Discrimination is on that body part. Then have the students measure the distance at which the subject reports "I feel 2 points". They will do this for all the body parts tested. After one student has performed the test, have the students switch roles.
TESTING AREAS:
Finger, lip, cheek, nose, palm, forehead, foot, belly, forearm, upper arm, back, shoulder, thigh, calf
Critical Thinking:
After the activity is finished you can have the students look at their data and determine what parts of the body are most sensitive? In other words, where on the body can 2 points be detected with the smallest tip separation?
The students will discover that the receptors in our skin are not distributed evenly on our bodies. Some places, like our fingers and lips, have more touch receptors than other parts of our body, like our backs. That is why we feel so much better with our fingers, than with our back.
*I found this activity on-line at
Neuroscience for Kids
http://faculty.washington.edu/chudler/chtouch.html
Jaime Sytsma
42. Inside Out Bag
Materials:
1 jar
1 plastic bag, 1-quart or smaller
Instructions:
1. Open up a plastic bag and stick it into a jar. Smoosh the bag against the sides of the jar, taking up as much
room as possible between the bag and the jar.
2. Fold the plastic bag outside over the lip of the jar and secure it with a rubber band.
3. Now, grab the center of the plastic bag and lift. The bag will not come out of the jar, at least not without a lot
of effort.
Howcome:
Assuming you fastened the rubber band nice and tight, it will be difficult, if not impossible, for air to travel from
the outside the jar to the space between the plastic and the jar. As you pull on the bag, you create more
space. This means there are fewer air molecules per unit of space in the area between the bag and the jar.
There is a conflict between the air molecules outside the jar pushing in on the bag, and the air molecules
between the bag and jar pushing out. The more you pull the bag out, the less push there is from the air between
he bag and the jar. At some point, even your strongest pull can't overcome the difference in air pressure
between the two sides of the bag. Your bag is stuck.
Cool Business Card
Materials:
1 bucket of water
2 business cards
1 candle
1 old crayon
matches
Instructions:
1. Light the candle and ask the class what will happen when you hold a business card over the flame. If
someone thinks the card won't burn, keep a close watch on that kid for the rest of the year.
2. Hold a business card just above the flame. It should catch fire within a few seconds.
3. Place your pile of crayon shavings on top of a second card. Ask the kids what will happen when you hold
this card over the flame.
4. Hold the card over the flame so the crayon shavings are directly above the flame. In a short time, the
shavings will melt. The business card won't even be scorched. This might be a good time to caution the kids
against trying this without adult supervision. No sense ruining your day with a burned-down house and a lawsuit
to boot.
Howcome:
In order for paper to burn, it has to reach a temperature of 451 degrees Fahrenheit. Crayon melts at a lower
temperature than that. In this demo, heat from the candle transfers to the paper, and heart from the paper
transfers to the crayon. As the crayon melts, it absorbs heat from the paper just as fast as the paper absorbs
heat from the flame. The paper never absorbs enough hear to reach 451 degrees, so it doesn't burn.
43. Spider Gliders
Carmen
Hall
The objective of this lesson is to teach the students about the scientific method. Spiders are the theme and they can be incorporated into many subjects. We could start by having the students walk around the school outside and observing everything they see. Then they could draw pictures and write a sentence about what it is they saw- this incorporates art and writing. We could read spider books and bring real spiders into the classroom to observe.
Our first experience with the scientific method would be with the spiders that were brought into the classroom. Any questions could be used.
Question: Do spiders eat only insects?
Hypothesis: We believe that spiders only eat insects.
Observations: We may only observe the spiders in our classroom eating insects, but we learned from books and the Internet that spiders can eat other spiders, birds and mice.
Conclusion: What we learned disproved our hypothesis
The teacher could then discuss force with the class. Force is an action, not a thing. Force by one surface on another is called friction. An object exerts a force on another object whenever the first object causes the second to accelerate. Our second experience with the scientific method would be with this information and spider gliders that we are going to make. We would show the students the spider glider that we made and ask the students to hypothesize about what will happen if the string that is through the straw exerts a force on the straw that is attached to the spider, what will happen?
Question: What will happen to the spider if the string that is through the straw on the spider exerts a force on the straw that is attached to the spider?
Hypothesis: The spider will move.
Observation: The students have to make the spider to see that this is true.
Conclusion: Our observations proved our hypothesis true.
Materials for Spider Gliders: construction paper, scissors, 5 yards of string per spider, masking tape, 1 straw per spider, 4 pipe cleaners per spider, crayons or markers.
Directions for Spider Gliders: Fold paper in half, draw half of each segment
of body of spider (remember we learned a spider only has 2 body parts- the head
and abdomen,) cut out body, unfold, decorate, cut straw in half to fit in the
abdomen area, tape the straw to the back of the spider, bend pipe cleaner for
legs, tape legs to body of spider, cut leftover straw in half, pull the string
through the straw on the glider (so two ends are at bottom of spider and loop
is at the head of the spider,) tape small straw pieces to ends of string, tape
middle loop of string high on a wall or in a doorway, now test it- pull the two
ends of the string apart and watch it climb.
Amber Vasquez
44. Cloud in a Bottle
Materials Needed:
· 1 Clear plastic 2-liter soda bottle (remove label)
· 1 Sheet black construction paper
· Hot water
· Matches (Be sure to have adult supervision)
Instructions:
· Pour 2 inches of very hot tap water into the 2-liter bottle
· Place your mouth over the opening and blow into it to ensure the bottle is fully expanded. Immediately seal the bottle tightly.
· Shake the bottle vigorously for one minute. This will distribute water molecules in the air.
· With adult supervision, light a match. Let it burn for two seconds, then drop it into the bottle. Quickly recap the bottle.
· Lay the bottle on its side with the black paper behind it. Press hard on the bottle for ten seconds. The bottle is strong, so don’t be afraid to really push hard. Release, observe, and repeat until cloud forms.
· When the cloud has formed, quickly unscrew the cap. You should see the cloud escape from the bottle. If not, give the bottle a light squeeze.
Scientific Principle:
By following the steps, you have created the conditions necessary for cloud formation: water vapor in the air, smoke particles for water to collect on, and cooling of the air by lowering the air pressure within the bottle. Voila! Instant cloud formation. Clouds form when condensation collects dust particles, which you provided with the smoke from the match.
Information on Air pressure:
Air pressure is the force exerted on you by the weight of tiny partic