We made these magic snowflakes to get ready for Frozen 2 this week and my daughter couldn’t get enough of them! They utilize differing solubilities of markers to make it look like color is coming out of nowhere!
Materials
Coffee filters
Black indelible marker
Washable markers (any color)
Eye dropper
Water
Method
Draw the snowflake with the black indelible marker.
Color over it with the washable color markers, being careful to stay only on the black lines.
Give it to your kids and have them drop water on to the snowflake to see the colors evolve and dance about!
Discussion
The black marker is not soluble in water so it does not run when you drop the water on it. The washable markers are colored by molecules that are soluble water, however, so they are lifted from the coffee filter and carried around the plate. It is a beautiful, surprising effect and one that can be modified for many other themes besides Frozen!
Teach kids about basic circuits and exercise their ingenuity by creating a DIY spin-art box from a cardboard box, motor, wire, and a battery!
Materials
Cardboard box
Scissors or box knife
Hobby Motor (The motors we have are no longer available, but this is a nice set that also includes, among other things, a battery holder, wires, and switch.)
Warning: Spinning cardboard or paper can cut you, be careful. When working with motors and batteries, follow all directions as outlined by the supplier to ensure your are using their product correctly and safely.
Procedure
Cut off the flaps of the cardboard box, trace and cut a large circle from one of them, marking the center of the circle.
Set up your circuit with the motor, battery and switch according to the motor’s directions (i.e. Make sure you are using the right battery for the motor). If you don’t have a switch you can connect and disconnect the battery to turn it on and off.
Mount the motor in the center at the bottom of the box with the motor shaft facing up. Depending on your motor’s casing, it may need to be mounted from the sides as opposed to the bottom because sometimes the back end of the shaft is exposed and will create friction on the box when running. This may be challenging, but it is exactly why you are making your spin-art box with your child instead of buying it- problem solving and creativity. We’ve done this several times and each time we try to think of a new way to mount it, including recycled Styrofoam blocks, a toilet paper roll, or one of the other flaps from the box.
Poke a hole in the center of the cardboard circle you cut and set it on top of the motor shaft.
Place a piece of duct tape over the shaft, pinch so it sticks to the shaft, then flatten the rest onto the cardboard.
Test your set up, making adjustments if necessary.
Cut your paper so it fits into the box, if necessary, then gently tape it to the spin platform.
If you’re using poster paint or acrylics, water them down a little so they are more fluid.
Turn on your contraption and squeeze paint as it spins!
Creating your own toys with your children fosters creative thinking, independence, and pride in one’s work. It also helps reduce waste and clutter in your home. Once you are done playing, you can dismantle your spin-art box, and reuse the motor and battery in many ways. Then, if you want to do spin-art at another time, set it up again!
Here are some projects from our site where you can reuse the motor:
This little project feels like something out of a sci-fi, which perhaps is why I love it so much. Add some magnetite powder to your next batch of slime, get a strong rare earth magnet, and your kids (or you) will have a blast making zombie worms and magnet eating monsters- straight out of the movies!
Safety: Do not ingest any part of this project. Do not use any of the materials around small children or children who put things in their mouth. Too much iron is poisonous and it should not be ingested in this form. Rare earth magnets are very strong and can pinch fingers, be careful when using them. Magnets should never be left around small children who could ingest them. Do not use magnets near electronics or credit cards. The magnet in the video has a pulling force of 48 lbs. This was more than sufficient. If you are doing this with kids, do not use a more powerful magnet and only use one magnet at a time to avoid pinched fingers.
In a bowl or cup, dissolve the 1/8 tsp borax in 1/4 cup hot water. Set aside.
To a different bowl, add 1/4 cup glue, 1/4 cup water, and 3 tbs iron oxide powder. Mix well. (Note: The powder will stain skin, so try not touch the iron oxide with your hands at this point, wait until the borax solution is mixed it. If you do get it on your hands, dish soap washes most of it off.)
Slowly add the borax solution to the glue mixture and mix well.
Take the slime out and knead with your hands till it is smooth. If it feels sticky, dip it in the extra liquid in the bowl and knead again.
Start playing with the slime and magnet!
The Science Behind Slime
The glue contains a long molecule called polyvinyl alcohol (PVA). It is a polymer, which is a molecule that contains repeats of a subunit molecule (for example, “A” is a subunit and “AAAAAAAAAAAAAAA” is a polymer of A). Borax (sodium tetraborate) is a small molecule that can stick to parts of the PVA through hydrogen bonds. This means one side of the borate molecule can stick to one strand of PVA, while the other side of the borate can also stick to a different strand of PVA, creating a bridge between the two PVA strands. This is called crosslinking.
Having many crosslinking sites usually makes a polymer more rigid, but the interesting thing about borate/PVA crosslinking is that the bond is transient, meaning it can easily break and reform somewhere else. This causes the slime to act kind of like a liquid and kind of like a solid. If given time, the PVA can ‘flow’ as gravity pulls and breaks the borate/PVA crosslinks. It acts like a slime instead of a true liquid because as the PVA molecules pass by more borate, they can momentarily bond to borate and another strand of PVA, slowing down the flow. If you pull the slime fast, you break all those bonds quickly, allowing the slime to act like a solid momentarily.
The Science Behind Magnetic Slime
The iron oxide powder in the link above is magnetite, which is a natural mineral made of iron and oxygen. Like many iron-containing compounds, it is attracted to a magnet.
The iron oxide particles in the powder will become suspended in your slime matrix. As the particles are attracted to the magnet, they will pull the slime matrix with them, causing a whole section of the slime to move with it. This makes for some really cool effects!
If you’re looking for a project to use some of the leftover ion oxide powder, try our DIY Magnetic Shapes!
This activity takes raised salt painting to a whole new level! In this twist, we use some secret ingredients that will make the special paint change color once it hits the salt!
The above picture was made entirely by my almost four year old. And even though this was the fourth picture she had made, the process was still as magical to her as the first time.
The secret to the color change is in the special paint. Instead of a true watercolor, we are using red cabbage juice! Red cabbage juice contains molecules called anthocyanins that change color when exposed to different pH levels. For more of the science involved, check out this post. The painting surface, which is usually just glue and salt in the classic activity, is actually different mixes of glue, salt, and safe household acids or bases in our version. You can create the picture beforehand for your child (like I did above in the mermaid video), or they can plan and create their own science art all by themselves (like the snowman further up).
Materials
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Containers to hold the salt mixes, with labels and spoons
Method
Making Red Cabbage Juice
There are several ways to get juice from a red cabbage. All of these methods make quite a bit of juice. We freeze leftover juice in an ice cube tray, then save the cubes to melt for future projects.
Just juice some in a juicer (if you have one).
Add about a quarter of the cabbage to a blender and blend with about a cup of water (adding more or less depending on how much cabbage you have). Then strain the liquid.
Bring ~2 cups of water with chopped red cabbage to a boil, turn off heat and let sit till it’s cool. Strain the liquid.
Making the Salt Mixes
You can safely access three colors of the red cabbage juice with household solid chemicals: blue-green, purple, and pink. Prepare the mixes in a bowls or cups. Don’t forget to label them. Make as much as you need, or save some for later. The amount you make will depend on how much glue you need to cover, but the mermaids above took about 2 tbs of each.
Acidic Mix (Pink): 1 part citric acid to 6 parts table salt
Alkaline Mix (Blue green): 1 part baking soda to 3 parts table salt
Neutral Mix (Purple): All table salt
Making Your Art
Draw your design on the paper with a pencil.
Decide which parts will be blue, pink, or purple.
Using the glue, trace the drawing on just the lines that will be pink.
Sprinkle the Acidic Mix onto the glue (with fingers or a spoon), then shake off the excess.
Using the glue, trace the parts of the drawing that will be blue-green.
Sprinkle the Alkaline Mix over the new glue, then shake off the excess.
Using the glue, trace the parts of the drawing that will be purple.
Sprinkle the Neutral Mix over the newest glue then shake off the excess.
Let dry for about 30 min (This is optional. It will still work when the glue is wet, but you just have to be careful to not smoosh it with the paintbrush otherwise acid or base crystals that get stuck to the brush may change the color of your paint stock when you double dip.)
Load a brush with red cabbage juice and touch it to the salt/glue lines. Keep dabbing until your whole painting changes color before your eyes!
If you try this, be sure to share your creations with us! Find us on Instagram and Twitter @cara_florance. Use the hashtag #IBravedTheElements and we might feature you!
Deep inside diapers lies an amazing molecule that can absorb hundreds of times its weight in water. It is called sodium polyacrylate and is an inert, skin-safe polymer that can provide loads of fun sensory play. Read on to learn what it is, where to get it, and what to do with it!
Materials and Methods
Sodium polyacrylate can be purchased as artificial snow (click here for to buy) or harvested from an unused diaper. To do the latter:
Cut the top cloth-like layer of the diaper (the part that touches the baby) right down the middle width-wise.
Fold it on the cut, cut side down and put it in a plastic tub.
Shake it until tiny white specks gather at the bottom of the container.
Remove the diaper.
Add water (with food coloring if you want) a little at a time and watch as the water is quickly absorbed into the growing mass.
For a lighter texture, add less water, for a slushy texture add more water.
Discussion
Polyacrylate, on the molecular level, is like a long string of negative charges. The sodium, which is positively charged, sits on these negative charges all along the string, which allows the polymer to coil and tangle up. When water is added, it displaces the sodium and nuzzles up with the negative charges. This causes the polymer strand to unravel, not only increasing the size of the gel, but also exposing more negatively charged sites so even more water can bind. This is why you get so much absorbent bang for your buck.
What to do with it?
Sensory Bins
Add cups and molds and make sand castle-like creations with the slush form (more water)
Add small world toys, like evergreen trees and arctic animals, to play with the lighter form (less water)
Initially make the snow without coloring, then give the kids squirt bottles with colored water to
Magic Tricks
Make water “disappear.” Put the dried sodium polyacrylate at the bottom of an opaque cup, show that it is “empty”, pour water in, then flip the glass upside down. The polymer should absorb the water, expand, and stay inside the cup, making it look like the water disappeared.
Fake Snow
You can inexpensively buy enough sodium polyacrylate that you can fill a kiddie pool (or larger!) sized area with fake snow that kids can play in for a Frozen themed party or what-not.
Fluffy Slime
Add it to your favorite slime recipe for a whole new feel
Get ready for all the rainbow heart eyes in this easy and gorgeous introduction to chromatography. 🌈😍 Recommended age 3.5+
This activity focuses on the concept of solubility and how an appropriate solvent can carry molecules along a stationary phase. Read on for some basic science and how to make some jaw dropping art!
Cut squares from a paper towel (four from a large sheet or two from a select-a-size sheet).
Find the center of sheet and using different color Sharpies, heavily color in dots around the center point. Make sure the dots have a lot of ink in them, but don’t puncture the paper towel.
Using the eye dropper, drop isopropanol onto the center of the paper towel and watch as the ink radiates out from the center. Keep slowly adding isopropanol to grow your chromatograph.
Use your science art to make new crafts or hang it up to display!
Extra Experiments and Questions
Try doing this with water instead of isopropanol. Does it work? What’s happening?
Try doing this with washable markers (like Crayola). Which works better- water or isopropanol?
Do you think this would work with crayons?
How does this relate to stain removal? Why can’t you wash Sharpie out of your clothes with water?
Try putting less ink on the dots and see if you can separate some of the colors within the ink. The success of this will vary on the markers/colors you use, but its worth a shot!
Discussion
Chromatography is used frequently in labs to separate compounds in a mixture. There are many types of chromatography but they are all based on a similar concept: a mobile phase carries your molecules of interest through a stationary phase, and based on the different interactions with the mobile and stationary phase, the different compounds can be separated. This experiment illustrates how a solvent (the isopropanol) can carry soluble molecules (the ink) through a stationary phase (the paper towel). After kids grasp this concept, you can move on to more delicate examples of chromatography like separating the components of fall leaves or a bouquet of flowers. See below for some key definitions to go over.
Definitions
Chromatography: A way to separate parts of a mixture by moving the mixture and a solvent (mobile phase) along a surface (stationary phase). Because the different parts of the mixture will “prefer” to be on the stationary phase or mobile phase differently, they travel at differing rates, causing the parts to separate.
Solubility: A demonstration really helps to explain this to kids. They first must know that everything is made up of smaller parts, like molecules, ions, or atoms. Mix sugar or salt into warm water and show them that it seemingly disappears into the water. Explain that the smaller parts are being broken off from the larger crystal and surrounded by water molecules, which keeps them suspended in the liquid. They are still there, we just can’t see them. Then try doing this with chalk or something else that is not soluble in water. They will be able to see the bulk either floating or sinking to the bottom. Explain that these things are insoluble. The sugar or salt have properties that make them want to associate with water, kind of like magnets sticking to each other, while the chalk molecules do not.
In this experiment, the ink from Sharpies is soluble in isopropanol but not in water. The isopropanol is called a solvent, and the ink molecules are called the solute.
MobilePhase: In this experiment, the mobile phase is the isopropanol. It carries the ink molecules along the paper towel through capillary action.
StationaryPhase: In this experiment, the stationary phase is the paper towel. If solute molecules interact strongly with the stationary phase, they will stick to it earlier than molecules with less attraction to it.
Share the art you create with this project on Instagram and join our community! Tag us and use the hashtag #IBravedTheElements for a chance to be featured!
I have this thing with plants. I dream of having a rainforest in my home one day, but until recently, I’ve had a pretty black thumb. I tried to grow many different house plants when I got my first place, but I killed every single one of them. From fungus gnat larvae bursting through the soil after I tried to set up a DIY home irrigation system from leftover LPLC parts, to hydrogen sulfide-producing bacteria in the soil of a philodendron making my little condo smell like the end-days of the Permian extinction, it was pretty much a comedy of errors.
Fast forward 8 years later, I have a fiddle leaf fig (Ficus lyrata) taller than me, a healthy, full rubber plant (Ficus elastica), and a huge snake plant (Sansevieria trifasciata) that are my pride and joy, along with several other newer plants dotting our home. I didn’t raise these plants without problems though. For example, the snake plant and I battled a nasty (I mean NASTY) millipede infestation soon after I first bought it (This is where Anna first learned to use tweezers at 2.5-years-old: picking baby millipedes out of the soil. Talk about honing those fine-motor skills).
Plant motherhood is not all glamorous foliage, but the most important thing I learned is that you can’t just buy any plant at Home Depot, water the crap out of it, and expect it to thrive. You have to learn what each plant needs: soil type (airy, dense, sandy, etc), light (high, low, morning, etc), watering (drainage, frequency, dry depth, etc.), general care (humidity, cleaning, pruning, etc). In doing so, I’ve really come to appreciate every little thing about my plants, from the different types of variegation on each leaf to the climate where they were originally from.
The amazing teacher and science communicator, Naomi Volain, created a beautiful website called Plants Go Global to educate and raise awareness about plants to help solve our planet’s environmental problems. A part of this movement is appreciating the beauty of plants and fighting “plant blindness”- where the plants we see everyday just fade into the background of our view, not focusing on the importance, diversity, and striking beauty of them. I have combatted my own plant blindness by becoming a plant mom at home, and I hope to pass this on to my kids by educating them on everything from house plants to vegetable gardens to plant anatomy and biodiversity. Visit the site for more information!
Recently, my snake plant was blown over by the wind from an open window and a long leaf snapped off. I decided to use it to make some new plants. The process is so simple that a three-year-old can do it (and she did). Read on below in the discussion for more about the science behind propagation through cuttings, and some tips to do this project with a child.
Materials
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Healthy mother plant
Pot or container with drainage
Proper rooting medium. This replaces soil for the time being (see below for why). The medium needs to be airy, light (not compact), well draining, non-nutritive, and moist. There are several ways to achieve this:
Method (How to make plant cuttings for propagation)
Put your cutting medium into the container.
Lay the leaf down and mark a dot every 4-6 inches (see the image to the right).
Cut just below the dot with sharp scissors. If you’re doing this with a child, try to show them the picture or describe the process to them without doing it for them. It is a good exercise in following directions. Needless to say, be careful with scissors and young children.
Prepare holes for the cuttings to go into the potting medium (i.e. wiggle a pencil in there to make a line the shape of the leaf). This is so you don’t rub off the rooting hormone when you stick the cutting in there.
(Optional, though recommended) Dip the dot-side of the leaf into rooting hormone (see discussion section for what this is). I would do this step myself for younger children, but older ones can do it, just make sure they wash their hands afterwards. If you dip the wrong side in, it will not grow.
Put the cuttings into the pot, dot-side down, about 1.5 inches deep or so the leaf won’t tip over. If the wrong side gets put in the dirt, it will not grow (which is why the dots are helpful).
Water, then cover with a plastic bag to keep it moist.
Keep the medium moist and warm, and soon (2-10 weeks) you will have roots! To check, very very gently tug on the leaf. If there is resistance, you probably have roots.
Gently dig up the roots and plant in normal potting soil. A new plant will begin to grow from a newly formed rhizome and pop up through the soil. Snake plants are slow growers, so this might take a while.
Don’t worry if your cutting dies instead of takes root. It happens. When we did this, only 2 of our 7 rooted (but we did this without rooting hormone because I couldn’t find it after our move).
Two of seven rooted. It is pretty obvious which ones have roots!
The roots grow right out of where you cut the plant! The white thing on the bottom of the pointy leaf is a new rhizome. This will grow under the soil, then produce a new plant.
This is the little baby plant that is growing from the rhizome above. We are still waiting on the other leaf to sprout a baby, but it’s looking good!
Discussion
There is SO MUCH science going on here, it’s crazy. I’ll go through some highlights.
This is an asexual process so your new plant and old plant will have the same DNA. Propagation through cuttings is a form of plant cloning. I think this is what they did with Groot in Guardians of the Galaxy II 😉
You want the medium that you put the cuttings into to be non-nutritive to discourage pathogen growth. I’ve also read that you don’t want the plant to take up any nutrients to discourage leaf growth and encourage root growth (so it’ll send roots out searching for more nutritive soil).
You want the cutting to be big enough that it can still get some energy from photosynthesis, but small enough that it’s stressed to encourage root growth. Four to six inches seems to be the sweet spot for snake plants.
Rooting hormone! Although many plants may still root without it, using rooting hormone will up your chances of success. Most commercial rooting hormones are indole-3-butyric acid.
Hormones are molecules that cells and tissues use to communicate. In this case, it signals plants to grow roots.
Stem cells (not talking about cells in the stem of plants, confusing, I know) are special cells that can form other types of cells. The process of a stem cell becoming a specific type of cell is called differentiation. Plants, humans, and all animals began from stem cells differentiating. In the stems of plants, there are partially differentiated stem cells (Stem cells in stems! They couldn’t think of a different word here?!) that when stimulated, will start differentiating down the path to create more root cells. The injury from cutting the plant is stimulus enough to start this process, but you can help it along by using rooting hormone.
For Kids
We all know the “seed in a ziplock bag in the window” project to begin to teach kids about plants, but there are so many other educational and fulfilling projects to do with them. Having them join in with typical houseplant or garden chores is a great way to teach them about plants, responsibility, and pride in your work (and also handling frustration when 80% of your cuttings die). It is also a great way to encourage a love and appreciation of plants, and to fight plant blindness! Snake plants are a great place to start because they are easy to propagate and hard to kill.
For this project, you want to make sure your child knows the main parts of a plant (roots, stem, leaves). It can be as simple as:
Roots get nutrients from the soil
Leaves make energy (carbohydrates) from sunlight through photosynthesis
Stems help deliver nutrients and carbohydrates throughout the plant.
The snake plant is a little confusing because the stem isn’t obvious, but it’s good to learn about the vast variation in plant life.
Depending on their age and science background, you can introduce some of the concepts above, like stem cells or how cells use molecules (the rooting hormone) to communicate. This is an easy yet powerful project that highlights some key concepts about plants and life.
Check out PlantsGoGlobal.com for more information and ideas about plants!
Use this free STEM printable to let your child play a fun microscope game while they are pretending to be a scientist! Perfect for preschool to elementary science programs, this is a fun, safe, and creative way to introduce the world of microbes to a child. It’s basically using a drinking glass to see through murky water to visualize the “microbes” below. I first saw this activity on the Instagram account of happicrafts.com (@happi_crafts) and knew I had to make a microscope version. The set up is simple and this can be combined with several other activities outlined below to keep them engaged and curious. The printable contains microbe illustrations from Baby Medical School: Bacteria and Antibiotics, an adorable introduction to the microscopic world.
Materials
Clear plastic bin (or glass casserole dish if you dare)
Drinking glass
Water with suds or paint mixed in to make it opaque
Baby Medical School: Bacteria printable
Procedure
Print out the bacteria printable
Place it under the clear plastic bin.
Fill the bin about an inch with water then mix a little tempera paint mixed in so the water becomes opaque. White paint plus any other color worked the best to make it cloudy for us.
Add a clear, flat bottomed drinking glass to the bin. You should be able to slide the glass around to find the various bacteria.
Describe what bacteria and microscopes are to your kid (see below), then let them at it!
How to explain bacteria and microscopes to your kids: Bacteria are tiny, itsy bitsy things that we can’t see with our eye but are very important. We have bacteria all over us and inside us. Sometimes we get a bad bacteria that makes us sick, but usually the bacteria that live with us work with our body to keep us healthy. There are also bacteria all around us, both indoors and outdoors. Scientist study bacteria to learn how they work, how some can make us sick, and how some can help us. A microscope is an important tool scientists use to study bacteria. It helps them see the tiny little things to learn more about them.
Just have them search around a see what they find!
Make a game out of it and take turns closing your eyes and sliding the cup somewhere. If you land on a good bacteria (happy faces), you get a point. If you land on a bad bacteria (angry face), you don’t get a point.
Set up some cups in another bin next to this one with watered-down paint that they can color mix, suds, or even vinegar and baking soda to play and experiment with. Then have them dump their concoction into the bacteria discovery bin to pretend to check it with the microscope.
Have them describe the features of the bacteria they see (colors, spots, etc)
Free Printable
Copy and save this JPG! Please feel free to use this for personal use but please contact me if you would like to distribute it. Enjoy!
In one bowl, dissolve 1/2 tsp of borax into 1/2 cup of hot water.
In the other bowl, mix 1/4 cup of glue with 1/4 cup water.
A tsp at a time, mix 4-6 tsp of activated charcoal into the glue/water mixture. It won’t mix in at first, but just keep stirring, it will eventually mix in! Just a minute or so of stirring. Stop adding when it’s black enough for you. Mix until thoroughly combined.
Add 12 tsp borax solution to the glue mixture a teaspoon at a time while stirring. This slow addition of the borax ensures a super smooth slime without the need for lots of kneading. You will know when to stop adding when all of the black glue mixture is in the ball of slime and there is none left in a puddle at the bottom of the bowl.
Pick up the glob and fold and squish a few times. You’re done! After you’re finished playing with it, store it in an air tight container. If it feels gooey after a few days, add a little more borax solution till you get the consistency you like. We think this gradual goo-ing might be due to the activated charcoal absorbing some of the borax (see below for what borax does!).
Discussion
The glue contains a long molecule called polyvinyl alcohol (PVA). It is a polymer, which is a molecule that contains repeats of a subunit molecule (for example, “A” is a subunit and “AAAAAAAAAAAAAAA” is a polymer of A). Borax (sodium tetraborate) is a small molecule that can stick to parts of the PVA through hydrogen bonds. One side of the borate molecule can stick to one strand of PVA, while the other side of the borate can also stick to a different strand of PVA, creating a bridge between the two PVA strands. This is called crosslinking.
Having many crosslinking sites usually makes a polymer more rigid, but the interesting thing about borate/PVA crosslinking is that the bond is transient, meaning it can easily break and reform somewhere else. This causes the slime to act kind of like a liquid and kind of like a solid. If given time, the PVA can ‘flow’ as gravity pulls and breaks the borate/PVA crosslinks. It acts like a slime instead of a true liquid because as the PVA molecules pass by more borate, they can momentarily bond to borate and another strand of PVA, slowing down the flow. If you pull the slime fast, you break all those bonds quickly, allowing the slime to act like a solid momentarily.
This is a fun, silly, and educational activity that any kid who likes to make noise will love. Using oobleck (a mix of cornstarch and water) and common household items, you will be able to visualize the sound waves made when you yell!
What we perceive as sound is a wave of pressure transmitted through air. When you yell, your vocal chords vibrate. The energy is transmitted by air molecules smacking into each other, until they they smack into your ear. There, you have cells that can convert the vibrations into electrical signals which are transmitted to and deciphered by your brain. In this activity, you will yell into a device that will transmit your sound waves from air into oobleck so you can see the waves!
Definitions
SOUND: Kids will probably know what sound is, but not scientifically. Sound is vibrations that travel through a medium (usually air) which are eventually heard by ears. Kids will need to understand that air, even though we can’t see it, is all around us and can be moved similarly to the way balls move, like billiards. Try waving your hand quickly so they can feel the wind it creates. You can tell them air molecules can move to carry the energy from your hand to their skin so they can feel it. Sound also travels through air in a similar way, but sounds are made when something is wiggling the air much fast than your hand can move it. Roll a ball into another ball and talk about how the energy is transferred when the first ball hits, and use this analogy for air transmitting sound.
VIBRATION: To young kids, I like to explain this as fast wiggles. Since you know your kid the best, to define this word, you can draw on experiences you know they have had like the vibration of an old car going down the highway. You can also put their hands on one end of a table and have them feel the vibration of you knocking at the other end of the table. They probably have experienced vibration, but just need to connect the word with the phenomenon.
Materials
cornstarch
water
empty paper towel or toilet paper tubes
tape
rubber bands
thin flexible material like plastic wrap, latex, thin rubber sheet, nitrile (I cut a square from nitrile gloves)
Method
Cut the paper towel roll twice diagonally, as seen in the picture.
Flip the two end pieces up to form a U shape, then tape them together. (Or make into whatever shape you want. You basically want to be able to simultaneously yell into it and see the flexible membrane. The one below is what my daughter made from toilet paper rolls.).
Clearly, it doesn’t have to look pretty.
Cut your thin flexible material into a square that will fit over the end of the paper towel tube.
Secure the square to the tube with a rubber band, making sure the membrane is taut like a drum.
To make the oobleck, mix about 2:1 cornstarch to water together (you can make a lot to play with it later, but for this activity, you only need about a teaspoon). You will know it’s the right consistency when you can smack the oobleck and it acts like a solid, but you can also slowly pour it as if it was a viscous liquid. Just add a little more cornstarch or water to get this consistency.
Put about an eighth teaspoon of oobleck onto the drum end.
Make all sorts of sounds into the open end of the paper towel roll and watch the oobleck dance about! Constant, steady low or high sounds work the best, but experiment to see what you can make!
Discussion
When you scream into your device, kinetic energy is being transferred from your vocal chords, through the air molecules in the tube, to the membrane, to the oobleck. Note how the oobleck is formed into different shapes depending on the pitch of your noise.
You can use this experiment to talk to your kids about eardrums (aka tympanic membrane) by comparing them to the membrane on the device. Just as the screaming-device-membrane transmits sound from air in the tube to the liquid oobleck on top, your eardrum essentially transmits sound from the air in the ear to liquid in the cochlea.
This project can also be done by wrapping a speaker in Saran Wrap, putting some oobleck on it, and playing your kids’ favorite songs. It’s a great visual introduction to rhythm, beat, and volume and will give them a whole new musical experience.
(use correct voltage for the motor)
(with pointed tip applicator)
or 
or boiling water and strainer
(any type is fine, but thicker is better)
(Ficus lyrata) taller than me, a healthy, full 
(Ficus elastica), and a huge 
(Sansevieria trifasciata) that are my pride and joy, along with several other newer plants dotting our home. I didn’t raise these plants without problems though. For example, the snake plant and I battled a nasty (I mean NASTY) millipede infestation soon after I first bought it (This is where Anna first learned to use tweezers at 2.5-years-old: picking baby millipedes out of the soil. Talk about honing those fine-motor skills).
and 
(optional, though highly recommended)
(
)
, 
, or 
in there for hours of fun!
