Tag Archives: science projects

Make Your Own Fortune Teller Fish

Homemade Cellophane Fortune Teller Fish (Anne Helmenstine)

Homemade Cellophane Fortune Teller Fish (Anne Helmenstine)

The fortune teller fish or magic fish is a fish-shaped strip of polymer or plastic that bends and twists when placed onto your hand. The fish is red, but there’s nothing special about its color. The polymer absorbs water from perspiration on your skin, changing it structure and warping the fish.

Whether the fish bends head-to-tail or side-to-side can be used for games, to answer yes/no questions or predict your personality. The toy is simple to make it yourself.

Homemade Fortune Teller Fish Materials

There are two different materials you can use to make a homemade fortune telling fish:

Sodium Polyacrylate Fortune Teller Fish

If you buy the toy, the fish is made from sodium polyacrylate — the same polymer used in disposable diapers and fake snow. You could collect the polymer, wet it, press it into a sheet, let it dry, and cut it into a fish shape. That seems like a lot of work! Another option is:

  1. Hydrate water gel beads, diaper-insides, or fake snow until they have absorbed water. Depending on the starting product, you’ll have either clear or white damp gel. If you used colored gel beads, it’s best to use beads of one color or else ones that mix together to produce an attractive hue.
  2. Place the gel in a blender and blend until smooth. You can add food coloring if you’d like a colored fish.
  3. Use a paintbrush to coat a piece of glass or metal (like a cookie sheet) with the liquefied gel. Let the polymer dry. You can apply an additional coat of gel, if you like.
  4. Gently peel the polymer off of the surface to get a thin sheet. This is harder than it sounds because the gel will act like a giant fortune teller fish, bending in response to the humidity of your hands.
  5. Use scissors to cut the gel into a fish shape. Be creative! Make shapes other than fish, too.

Cellophane Magic Fish

The magic fish was invented before sodium polyacrylate was made. The original fish was made using cellophane, which is a thin sheet of transparent cellulose. You can use cellophane to make your own fortune telling fish. The only requirement is that you use real cellophane (sometimes called cello) and not colored plastic wrap or gift wrap. Amazon sells cellophane sheets or you can find them at arts and crafts stores.

  1. Use scissors to cut a piece of cellophane into a fish shape (or whatever you like). A good size is about 3-inches in length.
  2. Cut some fish one direction and some fish the other direction on the sheet. Why? Whether you use sodium polyacrylate or cellophane, a fish will one bend one way. The direction it bends depends on the orientation of the polymer.

Do you want to compare your homemade fish to the original product? The fortune teller fish toy is available from several sellers on Amazon.

How the Fortune Teller Fish Works

Supposedly, if the fish bends its head and tail together, this indicates a friendly personality, while curling sides indicates a mean spirit. Of course, there’s no magic. It’s all a matter of science.

Sodium polyacrylate and cellulose are polymers that readily absorb water. The cross-linking of the polymer subunits forms chains. The orientation of these chains determines which direction any particular fish will bend. Another common example of cellulose is newspaper. It’s easy to tear a newspaper into strips from top to bottom. If you tear across the paper, you can see the jagged edges of the fiber. The magic fish is like newspaper, except the material is much thinner so absorbing a tiny amount of water warps the shape.

The Magic Fish and Science Education

The fortune telling fish is a great science toy because it makes kids (and adults) think! You can hand out the fish to a classroom and ask students to propose a hypothesis to explain how the fish works. While it’s water (hydration) that moves the fish, it’s common to think it might be static electricity, a temperature effect, or interaction with some other chemical in skin (oil or salt) that causes the movement. Ask students to design an experiment to determine the cause of the movement.

See How to Make a Fortune Telling Fish

How To Shrink a Quarter Using Electricity

If you apply enough electricity to a coil, you can use the electromagnetism to shrink a quarter. (Matthias Shapiro)

If you apply enough electricity to a coil, you can use the electromagnetism to shrink a quarter. (Matthias Shapiro)

One of the key properties of metals is that they typically conduct heat and electricity extremely well. There are countless practical applications of conductivity, plus some cool science projects. One of the more interesting projects is shrinking a quarter using electricity. Actually, it doesn’t need to be a quarter, but this coin is large enough that you can see a significant difference in its size after it has been zapped. The diameter of a quarter shrinks so it’s about the same as a dime. Here’s what you do and how it works:

Materials You Need

  • coin (or other piece of metal containing a conductive metal or alloy, such as aluminum, copper, or silver)
  • heavy-duty wire coil (the heavier the better)
  • electromagnetic conductor (seriously strong… like a couple thousand volts)

Let’s Shrink a Quarter!

  1. Place the coin very close to the wire coil. There should be no contact between the wire and the coin (i.e., close, but not touching).
  2. Discharge current through the conductor. The best way to do this is using a high voltage capacitor. This produces an extremely strong, quickly oscillating electromagnetic field surrounding the wire coil.
  3. The electrical field of the coil is associated with an extremely strong magnetic field, which changes the shape of the coin. It’s electromagnetic pressure. The mass of the quarter is unchanged — only its dimensions change. While the quarter is a smaller diameter, it’s thicker. The difference in size depends on the composition of the coin and how much current you run through the conductor.

Note: When you shrink a quarter, it will also be extremely hot! Wait for it to cool down before handling the coin.

How It Works

The quarter shrinks because the set-up applies what is called high-velocity electromagnetic forming (also called EM forming or magneforming). When the technique is used for commercial applications, high energy capacitors are discharged through a coil of wire. The rapidly changing electromagnetic field that is generated acts as a force to change the shape of metal near or inside the coil. The better the conductor, the more effective the process is. The best results are seen with silver, copper, and aluminum, but nickel, steel, and various alloys work to a lesser extent. There is an equal and opposite force to the one pressing in on the coin. This force acts on the coil winding. If the coil isn’t strong enough, it will blow apart. The coils are only good for one attempt.

It’s worth noting a similar effect occurs when a substation power transformer short circuits. The windings of the transformer may blow apart violently.

See a Quarter Shrink from Electricity

A lot of people think the shrunken quarter is a hoax. Discovery made a video of the process. They ran a camera at 100,000 frames per second to try to capture the shrinking process. Here’s how that went.

Not good enough? Here’s another video attempt at 100,000 frames per second, presented by amateur scientists at Hackerbot Labs in Seattle. In this video, you can see the green flame as the copper in the coil they used vaporizes.

So, as you can see from the videos, this isn’t a project you can replicate on your own without a bit of preparation and safety gear. If you do decide to go ahead, Stoneridge Engineering has some tips. They also address whether or not it’s illegal to alter currency.

Peep S’mores Easter Science Project

When you microwave Peep s'mores (or any marshmallow) the water vapor inside the candy expands, forming a hot foam. (Qfamily)

When you microwave Peep s’mores (or any marshmallow) the water vapor inside the candy expands, forming a hot foam. (Qfamily)

Happy Easter! Here’s a simple recipe for Peeps™ s’mores and a look at the science of why Peeps get so crazy big in the microwave.

Peep S’mores Ingredients

  • graham crackers
  • Peep candies
  • chocolate kisses (or chocolate bar pieces)

The recipe is easy and fun. Take a graham cracker, set a Peep on it, put a couple of Hershey’s Kisses™ on another cracker, pop them in the microwave, and nuke them until the Peep has expanded so it looks like it’s ready to explode (20 seconds seems good). Smush the Peep side and the Kiss side together, and enjoy!

Peep S’mores Science

Peeps are marshmallows, which are puffed table sugar. Table sugar is purified sucrose. Sucrose, like other sugars, is composed of hydrogen, carbon, and oxygen atoms bonded together. When you microwave Peep s’mores, the energy added to the candy causes the molecules to vibrate. The bonds holding sucrose together loosen, softening the marshmallow, while the water vapor inside the candy expands, exerting pressure on the sugar. Expanding water forms bubbles that cause the Peep to get larger and larger. If you leave the microwave on too long, eventually you’ll supply enough energy to start combustion of sugar. This reaction between oxygen and sucrose leaves you with a burnt marshmallow, and possibly a small fire in your appliance.

Here’s a bit more about sugar for you, to read for the 20 seconds it will take you to nuke a s’more and unwrap Kisses for another one:

Make Fake Glass – If you heat sugar, you can make hard candy out of it. If you spread the hard candy onto a cookie sheet, you can make stage ‘glass’.

Grow Sugar Crystals – Rock candy is made from sugar crystals. These crystals are fairly easy to grow, plus you can eat the finished product.

Experiments on Peeps – Neat website that discusses experiments on Peeps.

DIY Glow in the Dark Nail Polish

It's easy to make homemade glow in the dark nail polish

It’s easy to make homemade glow in the dark nail polish.

Make DIY glow in the dark nail polish that glows better than anything you can buy in a store. No black light needed! There are two methods that work really well, so you can pick the one that works best for you.

Using Glow Paint As Glowing Nail Polish

For the nails in the photograph, what I did was apply a clear base coat, let it dry, and then applied acrylic glow in the dark paint from a craft store. To get bright, even coverage, you’ll need 2-3 coats of paint. The brightest glow paints do not have any extra color (it would block the light), so if you want your nails to be colored under ordinary light, you’ll want to apply a regular nail polish first and then paint the glow on top of it. I took a picture of my hand in normal light, so you can see what to expect. The crystals that produce the glow add a bit of sparkle, but otherwise my nails look ordinary.

Glow in the Dark Nail Polish Materials

The other method is to mix up glow in the dark nail polish using clear polish and glow powder.

  • glow powder
  • clear nail polish or top coat
  • toothpick
  • old nail polish brush or small paint brush
Glow pigment is uncolored, so glow-painted nails look normal to slightly white under ordinary light.

Glow pigment is uncolored, so glow-painted nails look normal to slightly white under ordinary light.

The two key ingredients are glow powder and nail polish. Glow powder is phosphorescent pigment. You want the powder because it will mix with the nail polish, while a paint or glue will not. Glowing glitter works, but it doesn’t glow very brightly, so I don’t recommend it.

Glow in the dark powder is available online from Amazon, United Nuclear, Glow Inc., etc. Just make sure the powder you buy glows in the dark. There is also “glow powder” that only glows under a black light. This fluorescent pigment looks great under ultraviolet light, but won’t really glow in the dark.

You want a clear polish for this project because any pigment in the product will mask and diminish the glow. You can paint the glow polish over painted nails, if you want color. Some types of glow powder are colored, too.

I recommend using an old nail polish brush for this. You can clean an old brush with acetone. You can also use a small paintbrush.

Make Glowing Nail Polish

You could mix the powder and the clear polish in the bottle, but you’ll need to add small glass or metal beads to mix the product (since they don’t come in clear polish). It’s less wasteful to just mix up what you need.

  1. Pour a small amount of clear nail polish onto a dish.
  2. Use a toothpick to mix in glow powder until you get a smooth, even mixture.
  3. Immediately apply the glow polish using a nail polish brush or small paintbrush. For the brightest effect, apply the glow polish over a coat of glitter, metallic, or pale pink/white polish. The metal or pale color will reflect back the glow and enhance it.

Top Science Kits for Kids

There are so many science kits for kids on the market, it’s hard to separate the ones that are educational and fun from the ones that are duds. Here are my picks for the top science kits on the market for 2016. I’ve added links so you can compare prices for the kits online, but many of these sets are also sold at stores, like Toys R Us, Michaels, Wal-Mart, Target, etc.

Tips for Choosing a Good Science Kit for Kids

  • To some extent, you get what you pay for, but that doesn’t mean an inexpensive kit is necessarily horrible. Usually, price is a big indication of how many uses you’ll get from a kit or the quantity of material. For more advanced kits, this indicates some pricey chemicals may have been used.
  • Check to see what materials you need to supply. This also ties in with price. Some science kits keep costs down by expecting you to bring some common household materials to the project. If you have these materials, great! If not, look for an all-inclusive type of set.
  • Certain brands are more reliable than others. Kits made by Smithsonian, Thames & Kosmos, and Steve Spangler are sure to offer fun as well as education. If you don’t recognize a brand name, that doesn’t mean it’s a bad science kit, but it’s a good idea to read reviews to help you decide whether the product offers what you need.

Overall Science Projects Top Pick – Smithsonian Mega Science Lab

Smithsonian Science Kit (image courtesy Amazon)

Smithsonian Science Kit – One of the best all-around science kits for kids. (image courtesy Amazon)

What I like about this kit is that it offers something for everyone. You can build a chemical volcano, grow crystals, make an Earth model, explore the weather, dig for dino bones, and explore microscopic science. Smithsonian also offers each of these projects separately, but the mega kit is an excellent choice for the well-rounded young scientist. I’ve had great experiences with all of their kits because the instructions are reliable and easy to follow and there is a lot of good information about the why and how, not just steps to follow.

Best Chemistry Kits – Thames and Kosmos Chemistry Kit

Thames and Kosmos C1000 Chemistry Kit (courtesy Amazon)

Thames and Kosmos C1000 Chemistry Kit (courtesy Amazon)

Thames and Kosmos makes chemistry kits for the kid (or adult) who wants to perform real chemistry experiments. All of their kits are good. The difference between the kits is the amount of materials and lab equipment included. Note these kits are not suitable for young children. This is real science, targeted to the pre-teen, teen, and adult crowd. If you’re looking for a true chemistry kit, these are the people who make them. I bought one of their higher-end kits for my own home chemistry lab. There are lots of experiments you can do!

Top Science Kit for Girls – Spa’mazing Science Kit

Spamazing Science Kit (Amazon)

Spamazing Science Kit (Amazon)

Sure, all the other kits are great for girls, too. This is the kit my science-oriented daughter recommends, because it combines science with fun and useful bath products. This is a great kit for a slumber party or a get-together with friends. It’s made by Scientific Explorer. I’ve had good experiences with their kits. You get enough materials to make lots of fun stuff, plus you learn how ingredients combine to make the products. Another excellent science kit targeted for girls is a perfume kit. These sets are also wonderful, but may cause problems if someone in the house is sensitive to fragrances. The spa kit is easier on the nose.

I’ve got more kits to add to this post, but other duties call. Look for updates! I’m especially psyched about a glowing crystal set I’ve tried.

How To Make Glow in the Dark Crystals

This quartz crystal glows in the dark. It's easy to replicate the technique to make your own crystals and gems glow.

This quartz crystal glows in the dark. It’s easy to replicate the technique to make your own crystals and gems glow.

You can make any clear or translucent crystal glow in the dark! Here’s how I made a genuine quartz crystal glow. You can apply this method to make other natural gemstones, glass, or plastic items glow. If you’d rather grow crystals that glow in the dark, try my glowing alum crystals tutorial. If you want to treat a crystal you already have, read on…

Glow in the Dark Crystal Materials

Technically all you need is a crystal and any phosphorescent paint, but if you want the crystal to glow very brightly, glow for a long time, and resist water and wear, you need three materials.

  • translucent or transparent crystal or gem
  • phosphorescent paint
  • lacquer (acrylic or polyurethane)
  • black light (not essential, but very helpful)
The glow treatment on this quartz crystal is invisible under normal light.

The glow treatment on this quartz crystal is invisible under normal light.

I used acrylic phosphorescent paint by Glow, Inc. and Sculpey glaze, but there are other products out there.

It is important that you choose phosphorescent (which really glows in the dark) and not fluorescent (glows for fractions of a second) paint. Your color choice is somewhat important. Strontium aluminate pigments (the awesome ones) glow most brightly in green and aqua. Blue is quite nice, but a bit darker. Violet and white are beautiful, but not nearly as bright and don’t glow as long. Red and orange are improved versions of zinc sulfide and fade very quickly.

Varathane and Future are good sealant choices. They dry clear and are durable. Clear nail polish is not recommended because it has the reputation of yellowing over time and reacting with some polymers. Some clear polishes may be fine, but the other options don’t cost more, so why risk it?

How To Make the Crystal Glow

  1. If you’re like me and using a pretty crystal you found in the ground, your first step will be to clean the stone and let it dry completely. If you think your stone is already clean, wipe it down anyway, to remove any residue.
  2. Identify the part of the crystal you want to glow. You may be thinking you need to treat the whole crystal in order to make it glow. Nope. You simply need to make part of the stone phosphorescent. What’s important is that this part of the crystal can receive light. For a piece of quartz, rose quartz, pale amethyst, citrine, cubic zirconia, acrylic, etc. this can be any part of the stone. Usually you’ll treat the back of the stone, causing it to appear to glow from within. You could also treat the top and/or bottom of the crystal. It’s up to you.
  3. Use a small paintbrush to apply a thick, even layer of phosphorescent paint to the selected surface. Again, don’t paint the whole crystal unless you want to hide the natural beauty of the stone. You don’t want to do that, right?
  4. Let the paint dry completely. I allowed half an hour.
  5. Apply a second coat. If you have a black light, turn it on so you can see how you’re doing and to identify areas that need more phosphorescent pigment.
  6. Again, let the treatment dry. Now, you should have a nice glow in the dark crystal. Either expose it to black light or else hold it out in the sun or under a bright indoor light or your cellphone flashlight to charge the pigment. Turn out the lights and examine your work.
  7. If you’re pleased with the glow, you can continue to the next step, which is sealing the stone. Otherwise, you may wish to apply another 1-2 coats of paint.
  8. Finally, you should seal the stone. There are 2 reasons for this. The first and most important reason is that modern phosphorescent pigments are destroyed when they come in contact with water. Theoretically pigment in an acrylic paint is already encapsulated and protected, but it’s better to be safe than sorry, or you might have selected a solvent-based paint that won’t protect your pigment at all. The second reason is because the phosphorescent particles need to be large to produce a good glow. This makes the painted surface gritty. Coating the crystal smooths out the surface so the treated area will look and feel natural. Also, I think the lacquer helps prevent chipping and wear of the coating.
  9. Use a paintbrush to apply a thin, even coating of sealant to the treated part of the stone. I stick with one coat and don’t paint the untreated parts of the crystal, but you can coat everything, if that’s your thing. Allow the crystal to dry completely. No touchy! You’ll leave a fingerprint in the sealant, which probably isn’t what you want.

Now comes the fun part. Enjoy your creation! You can leave it on a desk and enjoy its glow whenever the lights go out, place it on a bathroom counter as a night light, or wire-wrap it for a pendant or a keychain.

What are you going to make?

How To Extract DNA From Human Cheek Cells

Animated DNA Molecule (brian0918)

Animated DNA Molecule (brian0918)

It’s easy to extract DNA from human cheek cells. You don’t even need a lab. Here’s how to do this experiment in your kitchen.

What Is DNA?

DNA is deoxyribonucleic acid. It’s the genetic material in every cell in your body, except mature red blood cells, which have lost their cellular nuclei. DNA codes for proteins, which are used to build structural material, such as teeth and bones, and also cells, which combine to form tissues and organs. Your DNA is unique to you!

Materials for DNA Extraction

  • sodium chloride (table salt)
  • liquid soap or detergent
  • distilled water
  • rubbing alcohol
  • yourself or a volunteer
  • a scale and a measuring cup or beaker for small volumes

How To Extract DNA

  1. First, you want to make an 8% salt solution. This means you dissolve 8 grams of salt in 92 milliliters of distilled water. If the salt won’t dissolve, you can microwave it for a few seconds to warm the water.
  2. In another container, mix together 25 milliliters liquid soap with 75 milliliters distilled water.
  3. Pour 10 milliliters of water into a cup. Swirl this water around in your mouth for 30 seconds to a minute.
  4. Spit the water into a small cup.
  5. Pour 1 milliliter of your salt solution into the cup.
  6. Add 1 milliliter of the liquid soap solution.
  7. Gently swirl the contents of the cup to mix them together.
  8. Pour 5 milliliters of rubbing alcohol down the side of the cup so that it slowly flows into the liquid.
  9. Within a few minutes, the DNA will rise to the surface of the cup as a cloudy, slimy-looking substance.
  10. Pour 1 milliliter of alcohol into a small, clear container (a test tube is great, if you have one handy).
  11. Use a glass rod or plastic toothpick to remove the DNA from its container. Do this by twirling the rod into the DNA, like twirling spaghetti onto a fork.
  12. Dip the rod into the container of alcohol. You may need to swish it around gently to dislodge the DNA you just extracted. That’s it!
  13. If you want more DNA, you can repeat the earlier steps and add the new DNA to the same final container. You’ll need to swish the water around in your mouth longer to get a good sample. Or, if you don’t really care about having the same DNA, add a sample from someone else’s mouth.

You can examine the DNA more closely using a magnifying glass or a microscope.

If you want to extract enough DNA that you can see and handle it more easily, try this easy DNA extraction from peas or spinach.