Author: Maddie Van Beek

You might think coffee tastes disgusting, but the majority of the adults in your life probably drink coffee in the morning! A big reason that people drink coffee in the morning is because of the benefits of caffeine. Caffeine is a substance in coffee (as well as some other beverages and food items) that is classified as a stimulant. This causes people to WAKE UP! when they drink their morning cup of coffee. If no one in your life drinks coffee, I’m sure you or a friend has had a caffeinated beverage such as Mountain Dew or Pepsi. Did you know that even chocolate has a small amount of caffeine? It’s true!
​
Our experiment today has less to do with coffee and more to do with the effects of caffeine on the body. In our activity, you will create an experiment to see the difference in effects between caffeinated and decaffeinated coffee on a variety of test subjects. Before we start that, let’s learn a little more about caffeine and what a stimulant does. ​

What is caffeine?
Caffeine is classified as a legal stimulant that appears in many beverages and foods that we consume. Check out the links below for information about how caffeine affects those who consume it.

http://kidshealth.org/teen/drug_alcohol/drugs/caffeine.html
http://science.howstuffworks.com/caffeine1.htm
 
What is a stimulant?
A stimulant is “a substance that raises levels of physiological or nervous activity in the body.” This means that stimulants make you more alert and energized, but also raises your heart rate and blood pressure.
 
How is coffee decaffeinated?
Decaf coffee doesn’t come from different “special” coffee beans. Normal coffee beans go through a decaffeination process in which steam or water is added that causes the bean to swell. This swelling allows for caffeine to be extracted. Read more in the link below.

http://coffeeandhealth.org/all-about-coffee/decaffeination/
 
Some people even say that caffeine can increase athletic performance! According to several sources such as
Runner's World, having caffeine before a workout can reduce an athlete's perceived exertion. Basically, you don't feel as tired. If you do take caffeine before working out, just make sure to also stay hydrated! 

Taking Pulse:
1. Find your artery on your wrist, right below your thumb.
2. Place two fingers of one hand over the other artery, as pictured above. (Do NOT use your thumb, as it has its own pulse. 
3. Count the beats for 10 seconds, then multiply by 6 to get the beats per minute. 

Now you can get started on your experiment! 

1. Gather 10 test subjects. A higher number is always better to get more accurate results, so if you can get more participants, go ahead! When you ask your subjects to participate, make sure you tell them to refrain from eating or drinking for two hours before the test. Why do you think this would matter?
2. Write your test subjects’ names on small slips of paper. Fold the slips and put them in a bag.
3. Draw out five names. These five will receive regular coffee.
4. Draw out the last five names. These five will receive decaf coffee. They are receiving a placebo. This means that they think they are receiving the regular treatment, which is normal caffeinated coffee, but they are really receiving decaffeinated coffee. Make sure you do not tell your participants whether they are receiving regular or decaf!
5. Write your test subjects’ names on the coffee cups.
6. Brew a pot of decaf coffee and pour it into the cups of the last five names you drew.
7. Brew a pot of regular coffee and pour it into the cups of the first five names you drew.
8. Now it’s time for testing!
9. Before you test your subject’s pulse, ask them about their normal caffeine consumption. Take notes on their response. Take your subject’s pulse before you give them any coffee. Write down the result.
10. Give your subject the coffee. Take their pulse 5, 10, and 15 minutes after drinking the coffee.
11. Move on to the next subject and repeat steps 9 and 10 until you are finished with all 10 participants.
12. Graph the pulse for each participant. The X-axis should be time and the Y-axis should be pulse.
13. Analyze your results. Trace your graphs for caffeinated coffee participants in green. Trace your graphs for decaffeinated coffee participants in red. Do the green graphs look different than the red ones? What does this tell you about caffeine’s effect on the body?
14. Look at the graphs again and trace the regular caffeine consumers in blue. Do these graphs look different from those who are not regular caffeine consumers? Did caffeine affect non-users more so than regular users?
15. How else could you test caffeine? Example: Have runners who regularly use caffeine run a mile without caffeine and record their time, pulse, and perceived exertion. The next day, repeat the process with the same subjects after they drink a cup of coffee. Does the coffee make a difference?

Schorzman, J., 2005. A small cup of coffee. 
https://upload.wikimedia.org/wikipedia/commons/thumb/4/45/A_small_cup_of_coffee.JPG/800px-A_small_cup_of_coffee.JPG File used in accordance with the 
Creative Commons Attribution 2.0 Generic License. Image was not changed. 

Jynto, 2011. Caffeine (1) 3D ball. 
https://upload.wikimedia.org/wikipedia/commons/thumb/0/05/Caffeine_%281%29_3D_ball.png/800px-Caffeine_%281%29_3D_ball.png File in the Public Domain. 

Haggstrom, M., 2012. 
https://upload.wikimedia.org/wikipedia/commons/thumb/0/07/Health_effects_of_caffeine.svg/800px-Health_effects_of_caffeine.svg.png File in the Public Domain. 

Pulse photo and running photo provided by Maddie Van Beek. 

Author: Maddie Van Beek

Art and science have some beautiful connections! Today we are going to get messy with several different kinds of watercolor painting!


Watercolor Oil Paintings​

You may already know that oil and water don’t mix. Today we are going to test that out in a fun art project. But first, why don’t these two liquids mix?
​
Check out this interactive link to learn more: 

Test it out! Fill a glass with about an inch of vegetable oil. In another glass, mix water with a few drops of food coloring. Pour the colored water into the glass and observe what happens! You will notice that the colored water sinks to the bottom. Dump the contents back into the other glass. What happens? No matter what, the oil eventually rises to the surface. This is because oil is less dense than water. Because water is more dense, it will always sink below the oil and the two will not mix.


To explore more about liquid density, check out our blog on creating your own rainbow in a jar with layers of liquid! http://www.discoveryexpresskids.com/blog/layers-of-liquid-density-create-a-rainbow-in-a-jar


Let’s get started on our painting!


YOU WILL NEED:
* Dishes, such as shallow bowls
* Liquid watercolors
* Vegetable Oil
* Watercolor paper
* Eye dropper
* Pan or tray


Here’s what to do!
1. Prepare your liquid watercolors in a few different dishes. Use as many colors as you would like.
2. Pour some vegetable oil in another dish.
3. Set your paper in a pan or tray (this gets messy!)
4. Use an eye dropper to drop splashes of watercolor onto your paper.
5. Use another eye dropper to drop vegetable oil onto your painting. Remember, oil and water do not want to mix, so the oil will move aside some of your watercolor and make for an even cooler painting!
6. Let your painting dry completely before moving.


Wax and Watercolors

You may have tried this before, but it’s always a fun way to create more textured paintings! You already know that water doesn’t mix with oil, but what about other materials? A while back, we experimented with different textures to see what materials absorbed watercolors.
Check it out here: http://www.discoveryexpresskids.com/blog/science-and-art-with-absorption


How well do you think water is absorbed into wax? Make a prediction!


YOU WILL NEED:
* Crayons
* Markers
* Paper
* Watercolors
* Paint brushes


Here’s what to do!
1. Draw a picture on your paper with your crayons, but leave some blank paper.
2. Draw a picture with washable markers, and again, make sure to leave some blank space.
3. Use your watercolors to paint over both of your pictures. What do you notice about your art? Is the watercolor absorbed into the paper? Does the watercolor mix with the wax? How about the marker?
4. You probably noticed that watercolor paint and marker blend together, but crayon resists the watercolor! This is because watercolor paint and washable markers are both water-based. The wax in the crayons does not mix with water, so watercolor does not blend with your crayon design. The wax is very similar to oil in that it is hydrophobic, or water fearing. Because wax is hydrophobic, it repels the water and does not absorb it.
5. Continue to create crayon/watercolor art! Have fun!


Creating Texture on Watercolor
Rubbing alcohol can be used as a cleaner or a sterilizer, but did you know that it can be used as a unique technique in painting? When applied to a wet watercolor painting, the alcohol repels the liquid watercolor, creating lighter spots. This can be a fun way to get creative textures! Let’s try it out!


Here’s a video tutorial if you want to see an example. Skip to 3:00 for a quick visual of what you’ll be doing: 

YOU WILL NEED:
* Dish, such as a shallow bowl
* Liquid watercolors
* Paint brushes
* Watercolor paper
* Rubbing alcohol
* Cotton swabs


Here’s what to do!
1. Prepare your watercolors.
2. Pour rubbing alcohol into a dish.
3. Create a watercolor design. Cover most of your paper with watercolor paint. Use as many colors as you would like!
4. Soak a cotton swab in the rubbing alcohol and dab lightly on your painting. You’ll notice that the rubbing alcohol repels the watercolor paint, so you’ll end up with a uniquely textured painting!
5. Use the rubbing alcohol to create more designs in your watercolor painting. Try dabbing, dropping, or spraying rubbing alcohol to see what kinds of affects you can create in your painting.
6. Let dry completely on a flat surface.


Image and video credits:
Laczay, B., 2006. Watercolours. Image uploaded from Wikimedia Commons on 1/29/2017. https://upload.wikimedia.org/wikipedia/commons/thumb/5/56/Watercolours.jpg/800px-Watercolours.jpg
File used in accordance with the 
Creative Commons Attribution 2.0 Generic License. Image was not changed. 

Barrios, J., 2007. Crayones cera. Image uploaded from Wikimedia Commons on 1/29/2017. 
https://upload.wikimedia.org/wikipedia/commons/thumb/4/4d/Crayones_cera.jpg/1280px-Crayones_cera.jpg
File in the Public Domain. 

Picanco, A., 2015. Watercolor Alcohol Technique Tutorial. Uploaded from YouTube on 1/29/2017. https://www.youtube.com/watch?v=_6t4aZpBYuk

Author: Maddie Van Beek

Normally we associate rain with the spring season, but with the recent warm winter temperatures in Fargo, we've had some January rain. No matter the season, the cool thing about rainy days is that they are often accompanied by beautiful rainbows! 

Did you know that rainbows are actually caused by refraction? If you want to learn more, check out our blog! 
​
If you want to learn more about rainbows, click the button below:

Another cool phenomenon that is seen more often in winter is a sun dog! Similar to a rainbow, sun dogs are also caused by refraction. Light is refracted from ice crystals and creates a halo around the sun. The sun dogs appear to the left or right of the sun, although they most often occur in pairs. So while you might not see too many rainbows in the winter, you can always look for sun dogs!

Now that you know more about rainbows, we're going to make our own... IN A JAR!

How will we do that?! Today, you will be experimenting with liquid density. The varying densities of different liquids will allow you to layer them without them mixing, thus, creating a “rainbow in a jar.” 


Before we try this fun experiment, you need to know a little bit about density. 


The density of a given liquid is determined by mass or how closely the molecules in that liquid are packed.


Density does not only exist in liquids, but in all states of matter. The density of a material is its mass per unit volume. What does this mean? 


The density equation shows us that density is mass (weight) divided by volume (the amount of space that a substance occupies):

Basically, this equation tells us that density is the amount of matter in a given space. 

In relation to our project, the density of a liquid is determined by how many molecules of that substance fit into a set volume. 


Think about it. Let’s say you put five gummy bears into a Ziploc bag for your little brother and 20 gummy bears into the same size Ziploc bag for yourself. Whose bag of gummy bears is more dense? 


A liquid with less molecules or smaller molecules is less dense than a liquid that has more molecules or larger molecules.
​

Which figure is more dense? 

If a liquid weighs more than than another liquid with equal volume, the heavier liquid has a higher density. The higher density liquid will sink below lower density liquids. Let’s check out an example that you are probably very familiar with. 


Demonstration: Pour 1/4 cup oil and 1/4 cup water into a glass. Which liquid sinks to the bottom (aka, which liquid is more dense?)


What does this tell you about these two liquids? 


This leads us into our activity for the day!


So you know that water is more dense than oil. Now, let’s try this out with a bunch of liquids. By using many liquids of varying densities, you can make a liquid rainbow in a jar!




YOU WILL NEED:

• Mason jar
• 1/4 measuring cup
• Food coloring (several different colors)
• Water
• Turkey baster or some form of dropper
• Olive oil
• Honey
• Corn Syrup
• Dish soap
• Rubbing Alcohol

Here’s what to do!

1. The first liquid that you will add to your jar is the honey. Use the 1/4 measuring cup to measure out 1/4 cup of honey, and then pour it into the jar. Make sure you pour it straight into the middle of the jar--be careful not to get it on the sides!
2. Rinse out the measuring cup. You will need to do this after each liquid is added. 
   
3. After the honey settles into an even layer, add the corn syrup (again, make sure to dump it in the middle without hitting the sides!). If you want your rainbow to be more colorful, mix in a few drops of food coloring with the corn syrup before you add it to the jar. 
4. Next, measure and add the dish soap. 
5. After the dish soap settles, measure and add the water. Again, add a few drops of food coloring to the water before adding it to the jar to make your rainbow more colorful! Use a different color than you did for the corn syrup so you can tell the difference. 
6. Next, you will measure and add the the olive oil. 
7. Last, you will measure and add the rubbing alcohol. You can use food coloring to color this liquid, as well! But wait! You will need to use the turkey baster or dropper for this one! Add the liquid in very carefully, so it doesn’t mix with the other layers. 
8. You’re done! You have your very own rainbow in a jar! 

Follow-up Questions: 

• What enabled you to make a liquid rainbow? 
• Explain why these liquids didn’t just mix together. 
• Were you surprised by your results? Why or why not? 
• Draw your liquid rainbow and label each layer to record which liquids are more or less dense. 

Extension: 

Try this out with different liquids! See if you can discover densities of other common liquids in your home.


If you need a visual, check out this video of the experiment you just tried! They use even more liquids than we did, so if you need more ideas, this video is a great resource! 

Image and video credits, in order of appearance

​Rolph, E., 2007. Double-alaskan-rainbow. File uploaded from Wikimedia Commons on 1/22/2017. 
https://upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Double-alaskan-rainbow.jpg/1280px-Double-alaskan-rainbow.jpg File used in accordance with Creative Commons Attribution-Share Alike 2.5 Generic License. Image was not changed. 

Gopherboy6956, 2009. Fargo Sundogs 2 18 09. File uploaded from Wikimedia Commons on 1/22/2017. ​
https://upload.wikimedia.org/wikipedia/commons/thumb/8/88/Fargo_Sundogs_2_18_09.jpg/800px-Fargo_Sundogs_2_18_09.jpg Image in the Public Domain. 

Kelvinsong, 2013. Artsy density column. File uploaded from Wikimedia Commons on 1/22/2017. 
https://en.wikipedia.org/wiki/Density#/media/File:Artsy_density_column.png ​File used in accordance with the CC Attribution-Share Alike 3.0 Unported. Image was not changed.

​Density example created by Maddie Van Beek.

The Sci-Guys, 2013. The Sci-Guys: Science at Home - SE1 - EP5: 12 Layer Liquid Density Tower. Video uploaded from YouTube on 1/22/2017. https://www.youtube.com/watch?v=4EMUsPJtCoc&feature=youtu.be

Author: Maddie Van Beek

Today, you are going to learn about supersaturated solutions and crystals! We touched on these concepts last week when we learned how to make Egg Geodes. This time, you will be making your own rock candy! ​

A solution is a group of molecules that are mixed together and evenly distributed (homogenous). This is a little different from a mixture, which is unevenly distributed (heterogenous). 

​
Check out this link to learn more about the difference between solutions and mixtures:

Follow-up questions:

• Where is sugar found?
• What is sugar made of? 
• What kinds of foods do you find sugar in? 

When you dissolve sugar into water, you are creating a solution. Your sugar is the solute, and your water is the solvent. ​

When a solution is supersaturated, it becomes unstable. The prefix “super” means that it contains more solute than the liquid can hold. Thus, a precipitate is created. A precipitate is a solid deposited from a solution. In this case, the precipitate is the sugar crystals. ​

​When you are creating rock candy, the supersaturated solution creates a sugar crystal precipitate. The other process that is going on is evaporation. As the water evaporates, your sugar-water solution becomes more and more saturated with sugar, thus creating sugar precipitate, aka ROCK CANDY!!!

Image and video credits (in order of appearance)
Amos, E., 2012. Rock-candy-sticks. File uploaded from Wikimedia Commons on 1/15/2017. 
https://upload.wikimedia.org/wikipedia/commons/thumb/6/6c/Rock-Candy-Sticks.jpg/1024px-Rock-Candy-Sticks.jpg File used in accordance with the CC Attribution-Share Alike 3.0 Unported. Image was not changed. 

Chris 73, 2012. SaltInWaterSolutionLiquid. File uploaded from Wikimedia Commons on 1/15/2017.
https://upload.wikimedia.org/wikipedia/commons/thumb/8/89/SaltInWaterSolutionLiquid.jpg/320px-SaltInWaterSolutionLiquid.jpg 
​File used in accordance with the CC Attribution-Share Alike 3.0 Unported. Image was not changed. 

Amos, E., 2012. Rock-Candy-Closeup. File uploaded from Wikimedia Commons on 1/15/2017.
https://upload.wikimedia.org/wikipedia/commons/thumb/9/98/Rock-Candy-Closeup.jpg/800px-Rock-Candy-Closeup.jpg ​File used in accordance with the CC Attribution-Share Alike 3.0 Unported. Image was not changed. ​

References:
​https://en.wikipedia.org/wiki/Supersaturation
https://www.exploratorium.edu/cooking/candy/rock-pop.html
https://www.acs.org/content/acs/en/education/resources/highschool/chemmatters/past-issues/archive-2014-2015/candymaking.html

Author: Maddie Van Beek

Once again, we are going to be using eggs to learn about science! In the past, we’ve used eggs to learn about osmosis and acid-base reactions.

Today, we are focusing on sedimentation and crystallization. After you learn about these concepts, you are going to make egg geodes! 

Geode: A rock containing a cavity lined with crystals or other minerals. 

First of all, sedimentation is...

The process by which particles (solute) suspended in a fluid (solvent) eventually come to rest due to the forces, such as gravity, acting on them. 

Note: The solute and the solvent (the particles and the liquid they are suspended in) come together to form a solution. As you can see below, over time, the particles (green dots) in the fluid settle to the bottom. 

Crystallization is....

The process in which solid crystals precipitate from a solution or melt (Crystallization can also occur when crystals form from a gas, but this is rare. In our activity today, we are focusing on crystals that form from a solution).  

Can you think of a time that you’ve seen crystallization in the real world? I can! Back in November of last year, we did a snow blog (to see it, click here)! Snow flake formation is just one form of crystallization. Another form of crystallization is with natural crystals or gemstones. This takes a LONG TIME. 

Check out this video to see crystallization in action!

Now that you know a little bit about sedimentation and crystallization, try it out for yourself!

You'll be creating your own geodes inside eggshells. They'll turn out looking similar to the geode below, except you get to make them whatever color you want! 

YOU WILL NEED:

• Eggs
• Push pin
• Bowl
• Small scissors
• White glue
• Small paintbrush
• Egg dye or liquid food dye
• Hot water
• Spoon
• Cup or container 
• Drying area (rack, plate, or newspaper would work fine)
• Alum powder (you should be able to find Alum powder at any grocery store)

HERE’S WHAT TO DO!

1. Have you ever blown out eggs before you decorate them for Easter? That’s the first step to making egg geodes! You will need to carefully poke a hole in both the top and the bottom of the egg with the push pin. When you poke the hole, wiggle the pin around a bit to make the hole bigger. This will make it easier to blow the egg out of the shell.


2. Hold the egg over a bowl and blow on the top of the egg. The egg inside the shell should come out the bottom of the egg into the bowl. You can either throw the egg away, or go ahead and make an omelet! I suggest using your resources to have a great breakfast while you create your geodes :] 

3. This part is tricky. Now that you have an empty egg shell, you will need to use a small scissors to break the shell in half the long way. Don’t worry about it being perfect. As long as you have somewhat of a bowl shape, you are good to go. If your eggshell completely shatters, just blow out another egg and try again!


4. Again, you will have to be extremely careful in this step! Use a piece of paper towel to wipe the inside of the egg clean. Next, use the small paintbrush to coat the inside of the shell with white glue. Before the glue dries, sprinkle the Alum powder generously over the glue so that it coats the whole inside of the eggshell. 


5. WAIT!!! Your eggshell has to dry completely before you can move on. Leave it to dry overnight. 


6. Up and at ‘em? Back to the grind! Measure two cups of water and heat it up. You can either heat it to boiling on the stove or put it in a microwave-safe container and heat the water in the microwave.  Two to three minutes on HIGH should do the trick. 


7. CAREFULLY pour the heated water into the cup or container that you plan on using to create your egg geodes. 


8. Use a generous amount of food coloring to dye the water--30-40 drops is sufficient. 


9. Add 3/4 cup of Alum powder to the colored water and stir it with a spoon until the powder is completely dissolved. 


10. Let the Alum solution cool down for approximately 30 minutes. 


11. Once the solution has cooled down, use a spoon to submerge your Alum-coated eggshell. Make sure the open side is facing up, and the eggshell is resting on the bottom of the container. 


12. Now, the waiting game! Leave your eggshell to sit in the solution for 12-15 hours. Make sure you place the container in a safe place where no one will knock it over! 


13. After 12-15 hours, prepare a drying area. Use a drying rack, newspaper, or paper plate. Use a spoon to remove the eggshell from the solution.


14. Check it out! How has your eggshell transformed? Make sure to take pictures and write down your observations!


FOLLOW-UP QUESTIONS

1. What happened to your eggshell? Describe the change it went through. 
2. How can you relate your eggshell’s transformation to sedimentation and crystallization? 
3. Try to explain the process your eggshell went through. 
4. When does sedimentation and/or crystallization occur in real life? 

Here’s another fun activity about creating Alum crystals that will teach you a little more about crystallization!

References:

• http://en.wikipedia.org/wiki/Crystallization
• http://en.wikipedia.org/wiki/Sedimentation
• http://www.marthastewart.com/343344/crystal-egg-geodes

Image and video credits, in order of appearance:
​
Juppi66, 2009. Ametyst-geode. Uploaded from Wikimedia Commons on 1/8/2017.
https://upload.wikimedia.org/wikipedia/commons/3/3b/Ametyst-geode.jpg File in the Public Domain. 

Van Beek, 2017. Image created by Maddie Van Beek. 

iseen, 2014. Beautiful chemical reactions - Crystallization. Video uploaded from YouTube on 1/8/2017. https://youtu.be/193qXKFMQR8

Heyde, 2007. Geode inside outside. Uploaded from Wikimedia Commons on 1/8/2017.
https://upload.wikimedia.org/wikipedia/commons/thumb/6/60/Geode_inside_outside.jpg/800px-Geode_inside_outside.jpg File used in accordance with the CC Attribution-Share Alike 3.0 Unported. Image was not changed. 

The Sci Guys, 2013. The Sci Guys: Science at Home: Crystallization of Alum - How to Grow Alum Crystals. Uploaded from YouTube on 1/8/2017. https://youtu.be/ojpCexbhxdU

Author: Maddie Van Beek

Christmas Yarn Ornaments: How does static electricity work?

Have you ever pulled a sweater over your head only to look in the mirror and find that your hair is sticking straight up?! This is caused by static electricity. Static is more prevalent in the winter time because the air is usually drier than in other seasons. 

​Less humidity = more static. More humidity = less static.

What is static? Static electricity occurs when there is an uneven balance of electric charges on the surface of a material. This uneven balance causes that material to either be attracted to something (if that something has an opposite charge) or repel from something (if that something has the same charge). For example, when you pull that fuzzy sweater over your head, it causes your hair to be negatively charged. Because your hairs are negatively charged, they repel each other--they want to be as far away from each other as possible, so they stick straight up!
​
Check out the link below for an in-depth explanation of what static electricity is. ​

10. Once you’re done covering your balloon, carefully roll it in the glue mixture and then place it on the newspaper to dry.

11. Repeat steps 9 and 10 until you are done creating as many ornaments as you want! Leave them to dry overnight.

​12. In the morning, use a pin to pop the balloons. You are left with a cool homemade yarn ornament! 

Image credits:
All images taken by Maddie Van Beek

Author: Maddie Van Beek

It's almost December and the weather will be getting colder! In Fargo, the roads and sidewalks can get pretty icy, so people take extra care with driving and walking in the winter. ​Have you ever seen salt on the sidewalks in the wintertime? Most of you probably know that salt causes ice to melt. People sprinkle salt on icy sidewalks to make them less slippery. Have you ever wondered how that works? That’s what we are going to find out today!

Why does salt melt ice?

When you dissolve salt in water, the water is harder to freeze. Usually, water freezes at 32 degrees Fahrenheit (0 degrees Celsius). When you add salt to water, it has to be colder than 32 degrees Fahrenheit in order to freeze. Thus, adding salt to water lowers the freezing temperature.
​
Watch this video to find out more about the science behind why salt melts ice: 
​

Check out this link for more information: 
http://science.howstuffworks.com/nature/climate-weather/atmospheric/road-salt.htm
 
Now that you know why salt melts ice, let’s test it out!
 
YOU WILL NEED:

• Clear glass
• Water
• Ice cubes
• String

 
Here’s what to do!

1. Fill your glass about ¾ full with water.
2. Add about 5 ice cubes.
3. Cut a piece of string about 1 foot long.
4. Dangle the string into the water and try to catch an ice cube. When you lift the string out, do any ice cubes stick to it?
5. Let’s try it again. Dangle the string into the water over the ice cubes. This time, sprinkle some salt over the ice cubes. Wait a few seconds, then lift the string up. Do any ice cubes stick this time? Yes! Why did the salt make the difference? Remember, salt causes ice to melt! When you sprinkled salt on the ice cubes, they began to melt, but the water around it quickly refroze. The refreezing trapped the string onto the surface of the ice cubes. See how many ice cubes you can catch at once!
6. Does more salt change the effect? Try it out!

 
Now that you know how salt affects ice, use this same science to make your own slushy without the aid of a freezer!
​
YOU WILL NEED:

• Fruit juice
• Ice cubes
• 1 Gallon Ziploc bag
• 1 smaller Ziploc bag
• Salt

 
Here’s what to do!

1. Carefully pour fruit juice into the smaller bag and seal it shut.
2. Put ice cubes into the gallon-sized bag and add the salt.
3. Place the sealed smaller bag inside the gallon-sized bag.
4. Seal the larger Ziploc bag shut.
5. Shake it up!!!
6. Remember, salt lowers the freezing temperature of ice, so it causes the ice to melt. As the ice melts, the salty mixture also becomes colder… just cold enough to freeze up your fruit juice!
7. Once your fruit juice reaches the desired slushy consistency, place the bag in the sink, remove the smaller bag from the larger one and rinse it off with cold water.
8. Open your fruit juice bag and enjoy your homemade slushy!

 
References
http://www.sciencekiddo.com/salt-melts-ice-experiment/
http://www.sciencekiddo.com/fruity-ice-slush/
https://www.highlightskids.com/science-questions/how-does-salt-melt-ice-and-snow
http://science.howstuffworks.com/nature/climate-weather/atmospheric/road-salt.htm
​https://en.wikipedia.org/wiki/Salt

Image and video credits, in order of appearance:

Soric, D., 2009. Salt shaker on a white background. Image uploaded from Wikimedia Commons on 11/27/2016. https://upload.wikimedia.org/wikipedia/commons/thumb/7/78/Salt_shaker_on_white_background.jpg/800px-Salt_shaker_on_white_background.jpg File used in accordance with the 
Creative Commons Attribution 2.0 Generic Image was not changed. 

Chhe, 2009. SEM image of a grain of table salt. Image uploaded from Wikimedia Commons on 11/27/2016. https://upload.wikimedia.org/wikipedia/en/thumb/9/9b/Single_grain_of_table_salt_%28electron_micrograph%29.jpg/800px-Single_grain_of_table_salt_%28electron_micrograph%29.jpg File in the Public Domain. 

Heidas, 2005. Schneepflug strasse hinten. Image uploaded from Wikimedia Commons on 11/27/2016.
https://en.wikipedia.org/wiki/Winter_service_vehicle#/media/File:Schneepflug_Strasse_hinten.jpg File used in accordance with the CC Attribution-Share Alike 3.0 Unported. Image was not changed

Reactions, 2015. How does salt melt ice? Video uploaded from YouTube on 11/27/2016. https://youtu.be/JkhWV2uaHaA

As you all know, this Thursday is Thanksgiving! Today, we are going to research the history of Thanksgiving, test out Squanto’s gardening methods, and learn how to track our daily diets! 

We all picture the first Thanksgiving as a day spent with the pilgrims and the Native Americans chowing down on a Thanksgiving feast. Did you know that there were actually several “first Thanksgivings?” 

Learn more about the American history of Thanksgiving!

What were the other “first Thanksgivings?” 

Did you know November is National American Indian and Alaska Native Heritage Month? What a great time to learn more about Native American history and culture, especially as we celebrate Thanksgiving! 

More information on Native American histories and tribes:

While Thanksgiving is a great time to spend with family and celebrate an abundance of food, it is also important to remember the roots of Thanksgiving. We don’t often remember the Wampanoag’s point of view during the first Thanksgiving. Take some time to consider how the Wampanoag’s might have felt when the first white settlers arrived. 

Quickwrite: Write in the perspective of a member of the Wampanoag tribe when the white settlers arrived at Plymouth. How do you feel?

The Wampanoags were the Native American tribe that befriended the settlers and accompanied them in the “first Thanksgiving” meal. Squanto was one of the Wampanoags that is well known for aiding the settlers in their time of need. One way Squanto helped out was to assist them in growing corn by using fish. Check out Squanto’s gardening methods!

Hypothesize: How might fish emulsion help or harm the growth of a corn plant? Will it really make that much of a difference? 

YOU WILL NEED:

• Water
• Corn seeds
• Fish emulsion
• Milk cartons 
• Scissors
• Soil

YOU WILL DO:

1. Use the scissors to cut the top off of two half-pint milk cartons (ask an adult for help).
2. Fill both cartons with soil. 
3. Read and follow the directions on your corn seed packet to plant one seed in each carton. 
4. Push the corn seed 1-2 inches into the surface of the soil. 
5. Label one milk carton “Control” and one milk carton “Variable.” 
6. Your control plant will be watered only with plain water. 
7. Your variable plant will be watered with a mixture of water and fish emulsion. 
8. Follow the package instructions on the fish emulsion to dilute it with water. 
9. Water your Control plant with water and your variable plant with the diluted fish emulsion. 
10. Place both plants in the sun. 
11. Water both plants each day and record your observations in a daily log. 
12. Measure both plants’ growth each day and record. 
13. What differences do you see in the two plants? 
14. Create a graph at the end of your experiment to show the differences in growth. 
15. Reflect: How did the fish emulsion make a difference in the growth of the variable plant? Why do you think this is? 

Now that we’ve talked about GROWING food, let’s think about EATING food! 

Did you know that the average American eats over 4,000 calories on Thanksgiving day?! Wow! To put that in perspective, the average diet is only about 2,000 calories/day. ​

Watch this video to understand calories in a Thanksgiving Day Meal: 

Now, here’s an idea of how many calories you should have in a day:

Keep in mind that physical activity increases your caloric need! Think of your body like a car--let’s say your car holds 15 gallons of gas. You fill it up with 15 gallons. If your car just sits in the garage, it doesn’t lose any gas, but if you go for a drive, it burns gas. Is your tank still full after a 200-mile drive? No! If you want your gas tank to be full, you would have to refuel. It’s the same way with your body! For example, if my daily caloric need is 2,000 calories, and I burn 500 calories on a run, then I should actually consume 2,500 calories so my body still gets the calories it needs to stay fueled.

Here’s more information about what you can do to have a healthy, balanced diet:

How many calories are in your daily schedule? 

Are you eating a balanced diet? 

Create a food diary to see what your diet is really like! The point is not for you to count every calorie you eat--the point is that when we pay attention to what we put into our bodies, we are more conscious of what we are consuming. Being cognizant of the way you eat will help you make healthy choices for YOUR body! 

Predict: 

How many calories do you think you eat in a normal day? 

Do you think you have a balanced diet? 

What do you think you eat too much of? 

What do you think you don’t get enough of? 

Each day for one week, write down everything you eat for breakfast, lunch, dinner, and snacks. Each time you write down a food, determine whether it is a fruit, vegetable, grain, dairy, protein or fat. 

At the end of the week, look back at your food chart and reflect on your diet. About what percentage of your diet is protein? Fat? Does your daily diet look like the My Plate recommendation? Are you getting enough fruits and vegetables? Being conscious of your diet is the first step to taking care of a happy, healthy body! 




Other References:

http://www.educationworld.com/a_lesson/02/lp286-03.shtml

http://www.loc.gov/teachers/classroommaterials/presentationsandactivities/presentations/thanksgiving/celebration.html#

http://www.tolatsga.org/Compacts.html#Wampanoag

Image and Video Credits, in order of appearance:

Brownscombe, J.A., 1914. The first Thanksgiving at Plymouth. Image uploaded from Wikimedia Commons on 11/21/2016.
https://upload.wikimedia.org/wikipedia/commons/thumb/9/98/Thanksgiving-Brownscombe.jpg/1024px-Thanksgiving-Brownscombe.jpg File in the Public Domain. 

1910. Squanto teaching. Image uploaded from Wikimedia Commons on 11/21/2016. 
https://upload.wikimedia.org/wikipedia/commons/b/bc/Squantoteaching.png File in the Public Domain. 

Franske, B., 2002. Traditional Thanksgiving. Image uploaded from Wikimedia Commons on 11/21/2016. https://upload.wikimedia.org/wikipedia/commons/thumb/0/04/TraditionalThanksgiving.jpg/1024px-TraditionalThanksgiving.jpg File used in accordance with GNU Free Documentation License. Image was not changed. 

Healthcare Triage, 2014. How many calories are in your Thanksgiving dinner? Video uploaded from YouTube on 11/21/2016. https://youtu.be/PEWCUVnng6Q

USDA, 2014. ChooseMyPlate.gov. ​https://www.choosemyplate.gov/

​

Gravy is traditionally made from the turkey drippings. Some people swear by adding flour to the turkey drippings, while some say that the addition of corn starch is the secret to perfect gravy. The truth is, either ingredient will work to thicken gravy because both corn starch and flour contain starch, which is the one necessary ingredient to thickening a liquid such as gravy. 

Remember, just last week we learned about starch! We used potato starch to create our own "magic mud!" If you missed it, check it out here: ​http://www.discoveryexpresskids.com/blog/october-31st-2016

How does starch work? 
Starch will thicken a liquid, but the catalyst for starch to thicken is heat (Remember, a catalyst is a helper that gets a reaction going). When heat is applied, starch grains take in liquid and swell, causing that liquid to become thicker. Without heat, starch grains won’t take in enough liquid to make a difference. 

To learn more, check out the following two links: 
http://www.thekitchn.com/food-science-how-starch-thicke-83665 
http://www.scienceinschool.org/2010/issue14/starch

​

Now that you know more about starch, let's make some gravy!

Make your own gravy

What works better, flour or corn starch? Predict which ingredient will thicken the water quickest. You don’t have to go to the trouble of making real gravy to test out these ingredients. Just use warm water, and you’ll get a similar effect. 


YOU WILL NEED:

• Two mugs or small bowls
• Water
• Corn starch
• Flour

Here’s what to do: 

1. Put 1/2 cup of water in each mug. 
2. Microwave both mugs of water for about 1 minute (the water should be warm, not boiling). 
3. Add 1 tablespoon of corn starch to the mug on the left, and 1 tablespoon of flour to the mug on the right. 
4. Stir both mugs. Did the consistency change? 
5. Keep adding flour and corn starch 1 tablespoon at a time, stirring after each spoonful. How many tablespoons of corn starch does it take for the liquid to get noticeably thicker? How many tablespoons of flour does it take? 
6. You should have noticed that it took way more flour (about twice as much) to get the same thickness as the mug with corn starch. This is because corn starch is 100% starch, but flour is a mix of starch and protein. 

If you continue to add starch to water, you’ll get a gooey substance that’s fun to play with. You can roll the starchy goop into a ball, but when you quit moving it will slip through your fingers like liquid! 

​If you’re looking for some messy fun, try out the first slime recipe in our blog: 
http://discoveryexpress.weebly.com/blog/two-times-the-slime-fun-with-polymers (you can continue to use corn starch instead of liquid starch). 


OR


If you want to try to make your own gravy, here’s a recipe to test out:
​http://saucepankids.com/index.php/2012/07/real-gravy-no-bisto-recipe/


Now that you know a little bit about starch and its properties, lets move on to our next activity. 


A few weeks ago, we did an activity called Iodine Clock Reaction. 


If you missed it, check it out here: http://discoveryexpress.weebly.com/blog/iodine-clock-reaction


In that activity, we combined iodine, starch, vitamin C, and hydrogen peroxide. Because of a chemical reaction, clear liquids suddenly became dark blue! In our activity today, we will use iodine to test certain substances for starch. If the substance contains starch, BINGO! the iodine will turn blue.

Image and video credits, in order of appearance

Rehemtulla, M., 2009. RoastTurkey. File uploaded from Wikimedia Commons on 11/6/2016. 
https://upload.wikimedia.org/wikipedia/commons/thumb/1/11/RoastTurkey.jpg/1024px-RoastTurkey.jpg​
File used in accordance with the Creative Commons Attribution 2.0 Generic license. No changes were made.

NEUROtiker, 2007. Amylose2.  File uploaded from Wikimedia Commons on 11/6/2016. 
https://upload.wikimedia.org/wikipedia/commons/thumb/2/21/Amylose2.svg/486px-Amylose2.svg.png 
​This file is in the Public Domain.

NEUROtiker, 2008. Amylopektin Sessel, 2008. File uploaded from Wikimedia Commons on 11/6/2016. 
https://upload.wikimedia.org/wikipedia/commons/thumb/8/80/Amylopektin_Sessel.svg/451px-Amylopektin_Sessel.svg.png This file is in the Public Domain. 

Yuri, K., 2006. Wheat starch granules. File uploaded from Wikimedia Commons on 11/6/2016. 
https://upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Wheat_starch_granules.JPG/800px-Wheat_starch_granules.JPG This file is in the Public Domain. ​

​Chart created by Maddie Van Beek. Uploaded on 11/6/2016. 

Author: Maddie Van Beek

Happy Halloween!!!

A few weeks ago, we used candy for a chromatography experiment. This week, we are using simple potatoes to create magic goop that’s fun to play with! This would be a great Halloween activity. The magic mud that you’ll be creating behaves similarly to the slime you concocted in an earlier post. If you missed this fun and messy experiment, check it out here: http://discoveryexpress.weebly.com/blog/two-times-the-slime-fun-with-polymers.


This weird slimy substance that you’re working with today is a non-newtonian fluid. Non-newtonian fluids behave very differently from normal liquids or solids. Instead, they sometimes behave like a liquid and sometimes behave like a solid. When you apply pressure to a non-newtonian fluid, it resists and behaves like a solid. As soon as you release the pressure, the fluid returns to liquid form.

Although many people have experienced creating non-newtonian goop with corn starch, the magic mud you’re creating today behaves in the same way. How will you create the same kind of substance with a potato? Potatoes actually contain starch. You will have to first remove the starch from the potatoes to create your magic mud.

​Here's a video example of what you will be doing:

Below is a picture of what starch looks like. Starch is part of many foods including potatoes and is the most common carbohydrate in the human diet.

YOU WILL NEED:
* Bag of potatoes
* Water
* Food processor (optional)
* Knife (if food processor is not an option)
* Saucepan
* Kettle
* Strainer
* Jar


Here’s what to do!


1. Find an adult to help you with this activity! You may need to use a knife and you will use the stove, so make sure to be work carefully!

2. Wash a bag of potatoes in the sink.

3. Put your potatoes in the food processor and grind them into small pieces, or have an adult help you chop the potatoes into tiny pieces with a knife.

4. Dump the chopped-up potatoes into a mixing bowl.

5. Heat about 6 cups of hot water in the microwave or on the stove.

6. Carefully dump the hot water over the potato bits in the mixing bowl.

7. Stir the potatoes for a few minutes. What do you notice happening as you stir? The water actually changes color.

8. After about two minutes, place a strainer over an empty clear mixing bowl. Pour the potato water through the strainer to separate the liquid from the potato bits. Pay close attention to the liquid in the mixing bowl! What do you see happening? After 10 minutes, the liquid separates into two layers. The bottom of the bowl is white, while the reddish-brown liquid stays on the top. The white stuff you’ve removed from the potatoes is the potato starch. The starch is the necessary ingredient in making your non-Newtonian magic mud.

9. When this separation has happened, dump the top layer of liquid into the dirty mixing bowl. You should be left with just some white goop. The white goop looks a little dirty, so we are going to separate it even further.

10. Stir in about a cup of fresh water with the goop and pour it into a clear jar. Shake it up for 30 seconds and then let the jar sit for 10 minutes. You should notice that, once again, the liquid separates into two layers. The impurities stay on the top while the white goop sinks to the bottom.

11. Dump out the top layer of liquid. This should remove the impurities. You’re left with a milky-white substance. What does this substance feel like? Play with it! What do you notice about it? How does it act when you apply pressure? Try to roll it into a ball. What happens when you stop rolling? You’ll notice that when you stir it or roll it, the substance seems more firm, but when you stop applying pressure, it looks more like a liquid.


Extension:
Now that you’ve created your magic mud, go one step further and make it glow!


YOU WILL NEED:
* Fork
* Tonic water
* Black light


Here’s what to do!


1. Leave your magic mud in the jar for at least 24 hours. It will harden from a goopy slime into a solid.

2. Before you recreate your magic mud, take a look at your tonic water under a black light. Turn the black light on and the lights in the room off. What do you notice about the tonic water? It should be a glowing blue! The reason the tonic water is fluorescent under black lights is because of the ingredient quinine. (Don’t worry, the quinine in the tonic water is totally safe and non-toxic.)

Fluorescent objects absorb ultraviolet light that we can’t see, but they emit light than we can see. Read more here: http://www.scientificamerican.com/article/shining-science-explore-glow-in-the-dark-water/

The quinine in tonic water causes it to glow under a black light, so anything you mix with tonic water will also fluoresce! We are going to use tonic water to make your magic mud fluorescent. Turn the lights back on and let’s get going!

3. Use a fork to break up the solidified magic mud. It will easily crumble into a white powder.

4. Carefully add tonic water into the white powder. Add small amounts at a time and stir until the powder returns to its former goopy consistency.

5. Play with your new goop. What do you notice? It should behave exactly as it did before you let it dry. Here’s the big difference: When you turn on a black light, your magic mud will now eerily glow blue! For more fluorescent fun: Remember when we used tonic water to concoct glowing beverages for Halloween? Check it out here: http://discoveryexpress.weebly.com/blog/halloween-science).



Image and video credits:
Ord, 2003. Jack-'o-lantern 2003-10-31. Image uploaded from Wikimedia Commons on 10/30/2016. https://upload.wikimedia.org/wikipedia/commons/thumb/a/a2/Jack-o%27-Lantern_2003-10-31.jpg/800px-Jack-o%27-Lantern_2003-10-31.jpg File used in accordance with Creative Commons 2.5 License. Image was not changed.

Thompson, 2014. How to make magic mud - From a potato! Video uploaded from YouTube on 10/30/2016. https://youtu.be/_0J4dRqg7CE

Kalaya, 2009. Cornstarch mixed with water. Image uploaded from Wikimedia Commons on 10/30/2016. 
https://upload.wikimedia.org/wikipedia/commons/thumb/d/d5/Cornstarch_mixed_with_water.jpg/1024px-Cornstarch_mixed_with_water.jpg File used in accordance with Creative Commons 3.0 License. Image was not changed.