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Snapshot of Adventure
Have you ever wondered why the sky is blue or how gravity
works or what makes a rainbow? S cientists wonder about
those things, too. Then, they figure out the answers using
experiments. S ome of those experiments are really fun
because they use stuff that is gooey, oozy, splishy, and splashy
—just the kind of stuff Bear S couts enjoy! In this adventure,
you’ll get to do some science projects that are a little bit
messy and really amazing. S o put on your lab coat, and get
ready to do some super science!
ANS WERING S CIENTIFIC QUES TIONS
S cientists try to create a fair test when they want to
answer a question. The steps below can help you
answer questions like a scientist:
1. Ask a question. (What do you want to discover?)
2. Do research. (What have other scientists already
learned?)
3. Make a good guess at the answer. (This guess is
called a hypothesis.)
4. Test your hypothesis with an experiment. (This is the
fun part!)
5. Decide whether your hypothesis was supported by the
information you collected.
6. S hare what you discovered.
REQUIREMENT 1 | Make static electricity by
rubbing a balloon or a plastic or rubber comb on a
fleece blanket or wool sweater. Explain what you
learned.
You may have walked across a carpeted floor to pet your dog
and gotten a shock. You may have taken off your winter hat and
found that your hair was standing straight up in the air. Those
things happen because of static electricity.
To understand static electricity, you have to understand atoms.
Everything around us is made up of very small things called atoms.
Those atoms are made up of even smaller things, including protons
and electrons. Protons have a positive charge, and electrons have a
negative charge. Each atom usually has the same number of protons
and electrons, but if two atoms bump into each other, electrons
from one atom can get rubbed off onto the other atom.
As you walk across a carpeted floor (especially if you drag
your feet), extra electrons build up on your body. When you touch
your dog, those electrons jump onto the dog, causing a little spark
of static electricity.
Why does your hair stand up when you pull off your winter
hat? That happens because all your individual hairs now have a
positive charge and are repelling each other. (This is like trying to
hold the positive sides of two magnets together.)
Static electricity also makes some things stick together, such as
hiking socks and dryer sheets. For this requirement, try to make
objects stick to an electrically charged balloon or comb. Blow up a
balloon or take a comb and rub it against a fleece blanket or wool
sweater. See what objects will stick to it. Discuss your findings
with your den.
Testing Static Electricity
Which of these objects will stick to a balloon or comb? Write
down your prediction and then write down what actually
happened.
REQUIREMENT 2 | Conduct a balloon or other static
electricity investigation that demonstrates properties
of static electricity. Explain what you learned.
For this requirement, find out which objects will follow a
balloon and which objects will be repelled by it. Charge your
balloon with static electricity by rubbing it on a fleece blanket or a
wool sweater. Then, hold it close to the objects listed on this page.
Discuss the results with your den.
More Static Electricity Tests
Which objects are attracted to a balloon? Which objects are
repelled by a balloon? Write down your prediction, and then write
down what actually happened.
REQUIREMENT 3 | Conduct one other static
electricity investigation. Explain what you learned.
For this requirement, fill a dry, empty plastic bottle with small
foam beads (like the kind in beanbag chairs). Stand in front of a
mirror, and rub the bottle on your head. What happens to the
beads?
Now, touch your other hand to the bottle. Do the beads move
toward your hand or away from it? Experiment with other objects
to check the reaction of the foam beads.
REQUIREMENT 4 | Do a sink-or-float investigation.
Explain what you learned.
Have you ever wondered if an egg will sink or float? Do you
think adding anything to the water would change the outcome?
Let’s find out!
Materials
Three large cups, about 8 ounces, all the same size
Three fresh eggs
2 tablespoons of salt
2 tablespoons of sugar
Water
A spoon
Instructions
1. Fill all three cups half full with water.
2. Stir the salt into the first cup and the sugar into the second cup.
3. Leave the third cup alone.
4. In the chart on the next page, write down what you think will
happen when you add an egg to each cup.
5. Add an egg to each cup. Observe what happens to each egg, and
write down the results.
Sink or Float
Will salt or sugar affect whether an egg floats? Write down
your prediction, and then write down what actually happened.
How did your predictions compare to what you observed?
Why do you think the eggs did different things?
This investigation shows how scientists use variables. A
variable is something that changes. By changing just one variable at
a time, you proved how sugar and salt affect how eggs float. The
plain water is called the control because it doesn’t change. Since the
control is the same in each cup, we can use it to compare the
results with the salt and the sugar.
REQUIREMENT 5 | Do a color-morphing
investigation. Explain what you learned.
You may have heard that oil and water do not mix. In fact, they
will actually push away from each other if they are in the same
space! To investigate this principle, you will mix some food
coloring into oil.
Materials
A large jar or clear vase
Water to fill the jar half-way
A measuring cup
A spoon
2 tablespoons of cooking oil
3 drops each of red, blue, and yellow liquid food coloring
Instructions
1. Fill the jar or vase halfway with water.
2. In the measuring cup, mix the oil and the food coloring together.
3. Pour this mixture slowly into the water, and watch what
happens.
What is happening? Since food coloring is water-based, it will
separate from the oil and float through the water in amazing color
morphs. If you have time, try different color combinations.
REQUIREMENT 6 | Do a color-layering investigation.
Explain what you learned.
For this requirement, you will create a rainbow in a cup using
sugar, water, and food coloring.
Materials
15 tablespoons of sugar
15 tablespoons of warm water
Red, green, blue, and yellow liquid food coloring
Six clear cups
A spoon
Instructions
1. Put five cups in a row on the table.
2. Add one tablespoon of sugar to the first cup, two tablespoons
to the second cup, three to the third, four to the fourth, and
five to the fifth.
3. Add three tablespoons of lukewarm water to each cup. Stir until
most of the sugar dissolves.
4. Add a drop or two of food coloring to the first four cups, one
color per cup. In the fifth cup, mix two colors.
5. Take the fifth cup (the one with the most sugar) and pour half of
its contents into the sixth cup (the one that’s empty).
6. Hold the spoon, bowl side up, against the inside of the sixth
cup. Slowly and gently pour half the contents of the fourth cup
onto the spoon. (Pouring onto the spoon keeps the two liquids
from mixing in the cup.) Do the same thing with the third,
second, and first cups.
What is happening? Adding sugar to the water causes it to
become denser as the sugar molecules take over the space. The
more sugar you add, the denser the water becomes. That’s why
you can “stack” the colored water as long as you pour it gently.
Snapshot of Adventure
What do Zimbabwe, Egypt, and Chile have in common?
Amazing music! The native peoples of those countries have
been making musical instruments for thousands of years.
We’re not talking guitars, pianos, and trumpets, however.
We’re talking instruments like the mbira, the sistrum, and
the rain stick.
In this adventure, you’ll use your imagination to travel to
these distant lands and learn how to make your own musical
instruments. By the time your journey is over, you’ll have
enough instruments to start your own band. Ready to go? Our
first stop is Zimbabwe, home of the magnificent mbira. Let’s
get this musical adventure started!
REQUIREMENT 1 | Make an mbira.
Welcome to Zimbabwe, a country in southern Africa! People
have lived here for thousands and thousands of years, including the
Shona people, who make up most of the population. If you go to a
party called a mabira in Zimbabwe, you’ll probably hear people
playing the mbira (pronounced em-BEE-ra), or thumb piano.
Traditional mbiras have 22 to 28 keys made of forged metal.
Your mbira will use bobby pins instead, but you’ll still get a good
idea of what an mbira sounds like.
Materials and Tools
A board about 6 inches wide and 8 inches long
Four craft sticks
Four bobby pins
Safety glasses
Brads or wire nails and a hammer
Adhesive tape
Wire cutters
Hot glue gun
Instructions
1. Glue two craft sticks side by side across the middle of the board.
2. While wearing safety glasses, cut each bobby pin in half. Trim
the eight pieces you end up with so each one is a little shorter
than the one before it.
3. Lay the bobby pin pieces on top of the craft sticks from
shortest to longest. Align their ends with the craft sticks. At
the other end, they will stick out different lengths.
4. Tape the bobby pin pieces down so they don’t move.
5. Glue the last two craft sticks on top of the first two. To make
the mbira sturdier, use the hammer to drive brads through the
ends of the craft sticks and between each pair of bobby pin
pieces.
6. Bend the bobby pin pieces up at about a 45 degree angle from
the board. Get ready to play!
How to Play
To play your mbira, just pluck the metal “keys” with your
thumbs. Since they are different lengths, they’ll make different
sounds. See if you can play a simple tune like “Happy Birthday”
or “Twinkle, Twinkle, Little Star.” How would you describe the
sound the mbira makes?
You can also try some investigations with your mbira. Instead
of using your thumbs, use a spoon or a craft stick to pluck the
keys. Does that make a difference? What if you put the mbira
inside a box and play it? Does the sound change?
REQUIREMENT 2 | Make a sistrum.
For our next instrument, we will travel 3,000 miles north to
Egypt and 3,000 years back in time. Here in ancient Egypt,
musicians used an instrument called the sistrum to play songs for
the pharaohs (the kings of Egypt). M any wall paintings from royal
tombs show sistrums being played.
The original sistrums were made out of bone, wood, and strong
plant fibers. We’ll use materials that you can find around your
home or get at a craft store.
Materials and Tools
Wire clothes hanger
Electrical tape
Two craft sticks
Some fishing line or thin wire (the kind florists or picture-
framers use is great)
Buttons, jingle bells, metal washers, and other small items
that have holes in them
Wire cutters
Instructions
1. Straighten out the curved part of the clothes hanger (the part
that goes over the closet rod). This will form your sistrum’s
handle.
2. Put the craft sticks on either side of the handle. Tightly wrap
electrical tape around the handle and both sticks. Start your
wrapping just below the craft sticks and end it just above the
craft sticks so they won’t slide up and down. The sticks will
make the handle more comfortable to hold.
3. With the help of an adult, cut the long side of the clothes hanger
in half using the wire cutters. Bend each side down so you have
what looks like a big letter Y.
4. On each side of the Y, wrap electrical tape around the pieces to
hold them together. Do this at the top and the bottom and two
or three times in the middle. Be sure to leave spaces for the
next step.
5. Attach a piece of fishing line or thin wire to one side of the Y.
String some buttons, bells, washers, or other items on the line
or wire. Then tie the other end to the other side of the Y. Do
this again in one or two other places like the picture shows.
How to Play
It’s easy to play the sistrum. Just shake the instrument or flip
it from side to side to make the items in the middle swish, jingle, or
clang together. Try to match the rhythm in a song. Was it easier to
match the beat by shaking the sistrum or by sliding it back and
forth?
What sound from nature does your sistrum make? See if you
can make it sound like the wind in the reeds (a type of plant that
grows in low marshy ground) or like the gentle running water of the
Nile River.
REQUIREMENT 3 | Make a rain stick.
For our last stop, we’ll travel to Chile, a long, narrow country
on the western side of South America where we learn how to make
a rain stick. People in the Diaguita (pronounced DEE-uh-GEE-tuh,
where the G sound is like in the word “geese”) tribe here have been
making rain sticks for many years. Rain sticks have also been made
by tribes in Panama, Ecuador, Peru, and other countries in Central
and South America.
The original rain sticks were made out of pieces of hollow
cactus. People cut the spikes off and drove them into the cactus
like nails. These spikes caught seeds and pebbles as they fell from
one end to the other, making an amazing rain-like sound.
For your rain stick, you’ll use a cardboard mailing tube. A
“maze” of wire and chenille stems will take the place of the spikes.
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