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human body

lungs

at-home learning

biology

anatomy

indoor project

science project

Breathe in. Breathe out. Do you feel your chest expand and shrink when you breathe? That change in size is how you get air into your lungs! It all has to do with the physics of air pressure, which you’ll investigate in this project. Build another working model of your own body with a <a href="https://www.kiwico.com/us/store/dp/mega-hand/6526" target="_self">Mega Hand</a> from the <a href="https://www.kiwico.com/us/store" target="_self">KiwiCo Store</a>! Engineer a giant articulated hand that moves with your gestures, and find out how linkages let a few simple parts do something surprisingly lifelike.

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Cut the necks off of two of the balloons.

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Cut one straw in half. Then, attach one balloon to each straw half. Use tape to seal it off. These will be your “lungs.” 

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Take the other straw and make a 2" (5.08 cm)&nbsp;cut on one end so that it is split in half. 

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Flip the straw around and make two 2” cuts on the other end so that it is split into four.

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Tape one “lung” on either side of the two-way split straw.

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Remove the bottle cap and make a hole in the cap large enough to fit a straw through it. 

We made the hole using a pushpin and then widened it with scissors. 

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Place your “lungs” inside the bottle, so that the balloons hang towards the bottom. Then, poke the four-way split end of the straw through the hole in the cap. Screw the cap back onto the bottle.&nbsp;

You may need to shorten your straw based on the size of your bottle. If it’s too long, shorten the straw so that the lungs are about 2” from the bottom of the bottle. Then, make the four-way split again.

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Cut the neck off of the last balloon and stretch it over the bottom of the bottle. 

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Pull on the bottom balloon to see a simulation of how lungs work!

Air pressure is a measure of how strongly air presses on things. It depends on a few factors, but one of the most important is volume, or the amount of space the air has. If you’ve ever pressed on a balloon to try to make it smaller, you’ve probably noticed that it gets harder to press the smaller you make it. That's because air pressure increases when you shrink the volume (like when you squish a balloon). The squished air pushes back harder against you. The reverse is also true: air pressure decreases when you increase the volume. Air always tries to balance out pressure, so it will move from areas of high pressure to areas of low pressure. Your body uses this fact to move air in and out when you breathe. To breathe in, you expand your chest. That increases the volume in your lungs, which lowers their air pressure. Air rushes in to balance out the pressure. Then to breathe out, you shrink your chest, raise the air pressure in your lungs, and let the air rush back out.&nbsp;

plastic bottle (with cap)

straws (2)

Scissors

balloons (3)

pushpins

Tape

Lung Model

mechanics

STEM

This mechanical muscle machine models how your bicep and tricep muscles make your arm move. By linking levers together, you can create a complex motion and get pumped! Download the printable <a href="https://icdn.kiwico.com/diy_ad/KiwiCo-Muscle-Machine-Printable.pdf">here</a>.

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Print the printable. Then, cut out the pieces. 

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Set the bicep and tricep pieces aside. Trace the rest of the pieces onto the cardboard and use the pushpin to mark where the holes are.

The holes are indicated by the small circles on the printable.  

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Use double-sided tape to stick on the bicep and tricep pieces on the oval-shaped cardboard cutout. Then, widen each of the marked holes with a brad. The brads should easily fit into each hole.

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Fasten the bobbins to the cardboard pieces with the brads as pictured. 

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Use another brad to connect the cardboard pieces (bicep and shoulder) as pictured.

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Fasten two brads to the cardboard piece (forearm) as pictured. 

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Cut two pieces of string about 18” in length. 

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Tie a loop-knot on one end of each string. Then, wrap the loop around the two brads on the forearm.

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Connect the cardboard pieces (forearm and bicep) as pictured.

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Thread the string onto the bobbins as follows: clockwise for the top string (bicep) and counterclockwise for the bottom string (tricep). 

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Use the pushpin to make a set of holes just above and just below the bobbins. Then, thread the zip ties through the holes. 

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Secure the cardboard arm to the bottle with the zip ties. Then, start experimenting! 

To move the arm up and contract the bicep muscle, pull on the top string. To move the arm down and contract the tricep muscle, pull on the bottom string. 

When you have gotten a hang of how the muscles work, see if you can pick something up! 

There are way more muscles involved in moving your arm than just your biceps and triceps. Extensor and flexor muscles run through your forearm to move your wrist around. The deltoids on top of your shoulder, the pectoralis major on the front of your chest, and the latissimus dorsi on your back all help move your shoulder around. Your body has 650 muscles!

Many muscle groups work in pairs like the bicep and tricep. Flexing one will move a limb one way, and flexing the other will move it back. Which other muscle pairs can you find?

Some to check out: flexing your foot up and down, bending and unbending your knee, moving your leg away from your body and back, and bending forward and backward.

printable

scissors

crate box (or cardboard)

pencil

push pin

brads (8)

bobbins (4)

string

double-sided tape

zip ties (2)

plastic bottle (or glass bottle)

water (optional)

Muscle Machine

quick experiment

experiment

heart

household craft

Curious about how your heart pumps blood? Use this model to learn about the right atrium and ventricle!Discover more about the science of pressure with a <a href="https://www.kiwico.com/us/store/dp/store-bottle-rocket-project-kit/4588" target="_self">Bottle Rocket kit</a> from the <a href="https://www.kiwico.com/store" target="_self">KiwiCo Store</a>! Assemble a launcher, rocket, funnel, and launch mixture to experience some extremely fizzy fun.

If you’ve ever squeezed your hand together to shoot pool water, you’re familiar with the basics of how your heart works. It’s a muscle that squeezes together to pump blood around your body! But shooting pool water with your hand is pretty messy and splashy. Your heart has to be a lot more orderly. In fact, because of how your body uses blood, your heart needs to pump blood in just one direction. Blood carries oxygen on it, and all the parts of your body need oxygen to work right. If the blood pumped backward, your body would get blood that had no oxygen in it!In order to keep your blood flowing in the right direction, your heart has two pretty cool design features: chambers and valves. The chambers fill with blood, then squeeze tight to pump it out. Each side of your heart has an entry chamber called an atrium and an exit chamber called a ventricle (so your heart has four chambers total!). The entry and exit chambers pump one after the other to push your blood forward.Each chamber also has an exit door called a valve. These keep blood from getting pumped backwards. When the ventricle contracts, the atrium’s exit valve closes so blood won’t push back into it. When the ventricle relaxes, its own exit valve closes to keep blood from spilling backwards into it. That way, the pumping of each chamber moves your blood forward! To see more about how the chambers and valves work, follow the steps to build this model.

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Cut the neck off of two balloons. Then, tape the cut end of the balloon neck closed. 

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Cut a very small slit (enough to insert a straw) in the neck of each balloon about ½ inch below where you taped. Then, insert a clear straw into the slit of one balloon. Set the other balloon aside. 

This should be a very tight fit. You may need an adult to assist you. 

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Cut the bendy straw so that there is about 1 ½ inches on either side of the bend. Then, cut the other clear straw in half. 

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Tape the bendy straw in between the two half-length straws. 

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Cut two small slits directly across from one another near the top of one of the balloon tops. 

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Insert the long straw and the bendy straw into the two slits. 

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Insert one of the half-length straws from the bendy straw into the slit of the balloon neck you set aside in step 4.  

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Stretch the balloon over the top of the small container with both straws inside of it.  

This balloon should be as tight as possible. You may need an adult to assist you. 

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Fill one of the cups about ¾ full with water. Then, drip about 5 drops of red food coloring into it. 

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Place the cup filled with water on the other end of the bendy straw and the empty cup underneath the other straw. Then, push down on the balloon and watch what happens! This is how the valves in your heart work. 

This particular model shows the right ventricle “receiving” oxygen-poor blood from the right atrium through the tricuspid valve and pumping it to the body through the pulmonary valve.

Do you know what makes the sound of your heart beat? It isn’t the heart muscles contracting (try flexing your biceps and see if that makes the same sound). It’s actually the valves in your heart opening and closing! The first sound from the valve between your atria and ventricles closing. The second sound is from the valve between your ventricles and the rest of your body closing. Doctors think those sounds go “lub-dub, lub-dub.” What do you think a heartbeat sounds like?

cups (3)

clear straw (2)

bendy straw (1)

water

red food coloring 

Pumping Heart

Valentine's Day

physics

learning activity

In honor of Valentine's Day, we decided to get a little messy and explore the science behind what the holiday is really about - the heart!Want to explore anatomy without the hassle of gathering materials? Dive into learning with a <a href="https://kiwico.com/us/store/dp/vet-starter-kit/3542" target="_self">Vet Starter Kit</a> from the <a href="https://www.kiwico.com/store" target="_self">KiwiCo Store!</a>&nbsp;

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Cut the neck of the balloon where the balloon starts to widen. 

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Fill a jar halfway with water and add 3 drops of red food coloring. This will act as the "blood" pumping through the heart!

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Stretch the balloon top over the jar. Keep stretching the balloon to make sure it is lays flat across the mouth of the jar.

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Use scissors to carefully snip two small holes into the balloon, about 1 inch away from each other. Make sure each hole is big to fit the width of the straw, but small enough so that the balloon is tight around the straw, preventing the air from escaping between the straw and the balloon.

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If you cut the holes a bit too big, use tape to patch the side of the straws. Also, tape the end of one of the straws. Now it's time to pump your heart! Place your heart pump on a tray (this is going to get a little messy!). Use your fingers to press down into the balloon between the two straws. Watch the blood pump out from the pink straw! Of course, the action of a real heart is much more complicated than this simple model, but your heart really is a pump! With every heartbeat, muscles in your heart contract and squeeze the chambers (or open spaces) within your heart, just like your finger poking into the balloon. This squeeze pushes the blood in the chamber and moves it out of your heart and into your arteries. In your balloon heart, the water "blood" gets pushed up and out the straw "artery". Your heart does this an average of 70 times every minute, pushing your blood all the way around your body and back to your heart again!

balloon

straws (x2)

Heart Pump

gift

Father's Day gifts

Mother’s Day gifts

Make someone's day by sending them this homemade "hug" in the mail. 

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Have your child lay on the piece of paper with their arms open like they are about to give a hug. Trace them with a pencil or crayon. 

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Have your child fill in the details of her face, shirt, hair, etc. with markers or crayons. This is the part that makes the hug really special because it's their own decorating and creating (even though it might not come out the way you envisioned it would). 

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Write a message on your hug. I wrote "A Hug from Me to You" on ours. If your child is old enough to, encourage him to write his own message. 

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Sign and send your hug in the mail to someone special. Ours went to Grandma and it made her day. She couldn't believe how big it kept getting as she unfolded it from the envelope. 

large roll of paper

colored pencils

Send a Hug

chemistry

food science

Why is soda bad for your teeth?  My kids keep asking why they can't have more soda.  The tooth fairy was kind enough to lend us some baby teeth for us to experiment with, and we got some very interesting results.

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Fill a jar with your favorite soda.  We have three favorite sodas in our house, so we put in Sprite, Dr Pepper, and Coke.  Then fill a jar with water.

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Put one tooth inside each jar.  (If the tooth fairy isn't kind enough to leave teeth for you, you can use eggs for this experiment...just make sure to keep the eggs refrigerated.)

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Over the next several days, take each tooth out and observe it under a magnifying glass.  Touch the teeth to feel any differences in them.  Describe what it feels like.

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After observing the teeth each day, write down the results of that day's observation.

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After you've observed the teeth for several days, talk about the end results.   (Our family observed for five days; at the end of the five days, the teeth looked very gross!) 

6 awesome human body projects for kids

Screen-free fun!