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indoor project

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

science project

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)

balloons (3)

clear straw (2)

bendy straw (1)

water

red food coloring 

Scissors

Tape

Pumping Heart

Valentine's Day

physics

learning activity

at-home learning

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

optical illusions

easy experiment

Have you ever wondered how your brain understands how far away an object is? Find out how your eyes work together to process information with this easy experiment that tests your ability to perceive distance!

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Make a small circle slightly larger than the width of a pencil with a pipe cleaner. Then, twist the ends of the pipe cleaner together.

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Make a small ball out of clay and use it as a stand for the pipe cleaner. 

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Repeat steps 1-3, making each circle slightly larger than the last until you have three pipe cleaners on stands. 

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You are ready to test your depth perception! Place the largest pipe cleaner stand onto a desk in front of you so that you cannot see the hole in the pipe cleaner. Then, close one eye and try to thread the pencil through the pipe cleaner. Now, try it with both eyes open. Try this with each size! If this is too easy, try threading a needle with one eye closed!

Humans have great depth perception thanks to the position of our eyes. Both of our eyes face the same direction, so the two eyes "see" overlapping images that are just slightly offset from one another. The brain is able to use this offset, or "retinal disparity," to calculate how far away an object is. (Animals whose eyes are positioned on the sides of the head, instead of the front, like horses, have poor depth perception).See for yourself: close one eye and focus on a nearby object. Then, switch which eye is open, again focusing on the nearby object. The nearby object's position should appear to shift — that's a large retinal disparity. Now, look at a distant object with one eye at a time (say, something over 30 feet away). Distant objects create very similar images on each eye, resulting in a small retinal disparity. The muscles that help simultaneously focus your two eyes can also provide cues to your brain about the distance of nearby objects - they have to work extra hard to focus both eyes on objects that are very close to your face, so you can literally "feel" the sensation of focusing on very up-close objects. With just one eye, your brain can't rely on retinal disparity, or feedback from the two sets of eye muscles, to help with depth perception. Instead, things like shadows, or the size of recognized objects (like a cat versus a car), are used to judge distance. These cues aren't quite as reliable for producing good depth perception as retinal disparity or muscle feedback from two eyes, but they'll work in a pinch, and improve with practice.

pipe cleaners

clay

Seeing Depth Perception

lungs

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. 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">Vet Starter Kit</a> from the <a href="https://www.kiwico.com/store">KiwiCo Store</a>!&nbsp;

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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)

pushpins

Lung Model

homemade craft

<h2>Make a model lung with balloons!</h2>What's something you do all the time, all day and all night, without even thinking about it? Breathing! In fact, you breathe more than 23,000 times in just one day. When you breathe in air, it travels to your lungs which separate out the oxygen your body needs. Your lungs then send back everything you don't need by breathing out. The oxygen is sent to your blood, where it's used to make the energy you need to do everything, like running, eating, and talking.

Have a grownup cut the bottle in half. The edge of the bottle can be sharp, so be careful!

Tie a knot in the end of one balloon and cut off the top.

Stretch the balloon over the end of the bottle and secure with a rubber band. Don't worry if your bottle squishes a bit, it'll still work!

Slide a straw into the other balloon and secure with a rubber band. Test it out! Blow in the straw and make sure the balloon inflates. If it doesn't, your rubber band might be too tight or too loose.

Push the balloon into the bottle. Press the modeling clay around the straw to hold it in place and seal the opening. Test it out! Blow one more time and adjust the clay until the balloon inflates.

Hold the bottle and pull down on the knot in the balloon. Watch the balloon inside the bottle. What happens?

Make a hiccup! Give the knot in the balloon a few quick tugs. Do you see the balloon in the bottle jump? That's what happens when you get the hiccups. When you hiccup, your diaphragm moves down quickly, which sucks air into your lungs – HIC! You've made a model lung with balloons!

What's going on? Under your lungs, a big muscle called the diaphragm is working hard to help you breathe! When you breathe in, your diaphragm moves down. This creates more room in your chest, which lets your lungs fill with air. Your model lung works the same way. When you pull the balloon knot down, that creates more room in the bottle. This lets the balloon inside the bottle fill with air, just like your lungs do!

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8 easy anatomy projects for kids

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