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

Author: Maddie Van Beek

​Thanksgiving is coming up! One of the most popular Thanksgiving staples are cranberries. Cranberries are small, red berries that grow on a shrub. They’re usually sweetened into a sauce or jam, often for Christmas or Thanksgiving.

At the holidays, you might see whole cranberries, jellied cranberries, or cranberry sauce. How can we use cranberries for science? Let’s find out!

Cranberry Reactions

Watch cranberry juice react with baking soda and lemon juice!

There are two reasons that cranberries are going to react in our experiment today. One, cranberries are acidic. As you might know, when acids and bases meet, a chemical reaction takes place. You’ve seen this happen when you mix baking soda (a base) and vinegar (an acid). What happens? Lots of fizzing and bubbles! Remember, those bubbles are releasing carbon dioxide gas as a product of the reaction. The second reason that you’ll see a special reaction from cranberries is because of their pigment, anthocyanin. Anthocyanin is what makes cranberries their deep red color. When the acidity changes in the juice, anthocyanin reacts by changing color! Today, you’re going to mix cranberry juice with baking soda and lemon juice to see how these ingredients react with each other.

YOU WILL NEED:
* Cranberry sauce, juice, or whole cranberries
* Baking soda
* Lemon juice
* Glass or container
* Measuring spoons


1. If you’re using cranberry sauce, make sure it’s thawed out and in liquid form. If you’re using whole cranberries, mash them up and add a little hot water to get a good amount of juice.
2. Pour the cranberry juice into a glass. You should have at least one cup of juice.
3. Predict what will happen when you add a spoonful of baking soda to the glass of cranberry juice.
4. Add the baking soda and observe what happens. Record your observations.
5. Predict what will happen when you add lemon juice to the cranberry juice.
6. Add two tablespoons of lemon juice and observe the reaction! What happened?
7. Record your findings.
8. Extension: Add different amounts of baking soda or lemon juice. Does that make a difference? Can you get the color to change even more? What happens if you add baking soda and lemon juice at the same time?


Cranberry Building

In this activity, you will use cranberries to build the tallest structure possible!


YOU WILL NEED:
* Fresh, whole cranberries
* Toothpicks


Here’s what to do!
1. Unwrap your cranberries.
2. Connect two cranberries with a toothpick.
3. Continue building and connecting cranberries to build whatever structure you want. See how tall you can make your building before it tips over!
4. Test out the strength of your structure by setting an object on top. See how much your structure will hold!
5. Challenge: Try rationing yourself to only 20 toothpicks. Using those 20 toothpicks, what shape will create the strongest structure? Try a few different structures and test which one is the strongest!


Cranberry Sauce Recipe

Here’s a great cranberry sauce recipe that you can use for the holidays! Impress your family by helping out with this traditional treat!


YOU WILL NEED:
* 12 ounce bag of cranberries
* Sugar
* Orange zest
* Pepper
* Water
* Salt
* Pan
* Stove

Here's what to do!
1. Empty your cranberries into a saucepan.
2. Transfer 1/2 cup of the cranberries into a small bowl. 
3. Add 1 cup sugar, 1 strip orange zest, and 2 tablespoons water to the saucepan. 
4. Stir over low heat until the cranberries soften and the sugar dissolves.
5. Increase to medium heat cook until cranberries burst. 
6. Reduce to low heat and add the 1/2 cup of reserved cranberries. 
7. Add sugar, salt, and pepper to taste. 
8. Let cool to room temperature before serving.  

Recipe from: 
http://www.foodnetwork.com/recipes/food-network-kitchens/perfect-cranberry-sauce-recipe.html

Image credits, in order of appearance:
Weller, K., 2005. Cranberry bog. Image uploaded from Wikimedia Commons on 11/13/2016. 
https://upload.wikimedia.org/wikipedia/commons/thumb/3/3a/Cranberry_bog.jpg/1024px-Cranberry_bog.jpg
File in the Public Domain. 

Cjboffoli, 2010. Cranberries20101210. Image uploaded from Wikimedia Commons on 11/13/2016. 
https://upload.wikimedia.org/wikipedia/commons/thumb/4/45/Cranberries20101210.jpg/1024px-Cranberries20101210.jpg ​File used in accordance with the Creative Commons Attribution-Share Alike 3.0 Unported license. No changes were made.

Veganbaking.net, 2008. Cranberry sauce. Image uploaded from Wikimedia Commons on 11/13/2016. 
https://upload.wikimedia.org/wikipedia/commons/thumb/0/07/Cranberry_Sauce_%283617909597%29.jpg/800px-Cranberry_Sauce_%283617909597%29.jpg 
File used in accordance with the Creative Commons Attribution 2.0 Generic license. No changes were made.

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.

Author: Maddie Van Beek

​What do you think of when you hear the word fall? Brisk air, warm apple cider, boots and scarves... We’ve done a few activities about leaves and why they change color, which is a huge part of fall scenery. If you missed these blogs, check them out here:
​
Leaf blog 1: http://www.discoveryexpresskids.com/blog/why-do-leaves-change-color
Leaf blog 2: http://www.discoveryexpresskids.com/blog/fun-with-fall-leaves-preserve-leaves-for-fall-projects


Another popular activity in the fall is pumpkin carving! Many families enjoy picking pumpkins from a pumpkin patch (or your local grocery store or farmer’s market) and then carving them for fall and Halloween decorations! Today we are going to learn more about pumpkins and explore a few different pumpkin science activities.


What is a pumpkin?
Pumpkins are part of the winter squash family. They can be eaten and are often used as fall decorations. Pumpkins are thought to have originated from North America, and are usually yellow to dark orange in color. You may not have known that pumpkins are a FRUIT (fruits have seeds, vegetables do not). Nutritionally, pumpkins are very low fat and high in vitamin A. Although pumpkins are usually 6-18 pounds, some pumpkins weigh over 75 pounds!

History behind pumpkin carving:
Pumpkin carving started as a tradition to ward off demons! They are often associated with witches, wizards, and Halloween folklore. Although many people carve scary pumpkins, feel free to carve any sort of fun shape or happy face into your pumpkin--make it your own!

Want to carve a pumpkin? Here’s what to do!


YOU WILL NEED:
A pumpkin
Adult help
Knife
Candle
Marker
Match


1. Ask a parent for help!
2. Use the knife to cut a circle around the stem of the pumpkin. The circle should be big enough to fit your hand through. Remove the top of the pumpkin.
3. Out come the guts! The “guts” of the pumpkin are the stringy innards and seeds inside the shell of the pumpkin. You need to scoop as much of this out as possible.
4. Save those seeds--they make a delicious healthy snack! Scroll to the bottom of this blog for an easy pumpkin seed recipe.
5. You may want to use a permanent marker to draw out your design on your pumpkin before cutting. This will make it easier to cut once you’ve started.
6. Use a sharp, long knife to cut your design out of your pumpkin. The knife needs to be long enough to get all the way through the wall of your pumpkin. Pop the cut-out pieces of your pumpkin out as you go and throw them away.
7. When you’ve finished your design, put a candle in the middle of your pumpkin. Light the candle and watch your design come to life! Happy Halloween!


Fun science, pumpkin style!


In a past blog, we learned how to make pumpkin slime! You may have made slime, or “oobleck” before, but in the spirit of fall, we used pumpkins for a fun seasonal twist! The slime that you create in this activity is a non-newtonian substance, which means it sometimes behaves like a liquid and sometimes behaves like a solid.
Check it out here: http://www.discoveryexpresskids.com/blog/fall-fun-make-your-own-pumpkin-slime




Pumpkin Volcanos
You’ve probably seen baking soda and vinegar react in other activities, but today we’ll create a reaction inside a pumpkin for some spooky Halloween fun! Baking soda is a base and vinegar is an acid. When acids and bases mix, they react and create carbon dioxide gas. In this case, you see the carbon dioxide gas produced by a mountain of foaming bubbles! Let’s try it out!


To learn more about acid-base reactions, check out our blog here:
http://www.discoveryexpresskids.com/blog/experimenting-with-eggs-acid-base-reactions-and-osmosis2648476


YOU WILL NEED:
Baking soda
Vinegar
Food coloring
A small to medium-sized pumpkin
Knife


Here’s what to do!
1. You may use your pumpkin from the previous pumpkin-carving activity, if you wish! If you haven’t yet carved a pumpkin, follow the directions below.
2. Use a knife (with the help of an adult) to cut a circle around the stem of your pumpkin. Make sure the circle is large enough to fit your hand through.
3. Remove the stem of the pumpkin and scoop out the guts!
4. Dump about a cup of baking soda inside the pumpkin. This is the base in your reaction.
5. If you want to make your pumpkin reaction even more exciting, add a few drops of food coloring to your vinegar.
6. Pour some vinegar inside the pumpkin and watch your pumpkin ooze colorful foam! (Remember, the bubbles form from carbon dioxide gas produced in the reaction between vinegar and baking soda). Try adding dish soap to make your reaction even foamier!


Reuse and Recycle: Grow a pumpkin out of a pumpkin!

YOU WILL NEED:
Small pumpkins (fresh, not rotted)
Dirt
Water
Knife


Here’s what to do!


1. Ask an adult for help to cut the top off of your pumpkin. Remove the stem.
2. Stuff the inside of your pumpkin with dirt.
3. Treat your pumpkin like a potted plant--water the dirt daily and wait for your pumpkin plant to start sprouting!
4. Once your plant begins to grow, plant the entire pumpkin in the ground outside. Dig a shallow hole and bury the pumpkin. Continue to monitor growth and water your plant. Soon enough, you’ll have your own pumpkin plant!


Pumpkin Seed Recipe:   
http://www.foodnetwork.com/recipes/food-network-kitchens/pumpkin-seeds-recipe.html




References
https://en.wikipedia.org/wiki/Pumpkin
http://thehomeschoolscientist.com/pumpkin-unit-study/


Image Credits
2009. Pumpkin 2007. Uploaded from Wikimedia Commons on 10/23/2016.
https://upload.wikimedia.org/wikipedia/en/d/d8/Pumpkin2007.jpg File in the Public Domain.


Schoenberger, 2007. CompetitivePumpkins. Uploaded from Wikimedia Commons on 10/23/2016. https://upload.wikimedia.org/wikipedia/commons/thumb/c/ca/CompetitivePumpkins.jpg/800px-CompetitivePumpkins.jpg File used in accordance with the Creative Commons Attribution-Share Alike 3.0 Unported license. No changes were made.


Vishalsh521, 2011. Pumpkin flower. Uploaded from Wikimedia Commons on 10/23/2016. https://upload.wikimedia.org/wikipedia/commons/thumb/6/6c/Pumpkin_flower.jpg/800px-Pumpkin_flower.jpg File used in accordance with the Creative Commons Attribution-Share Alike 3.0 Unported license. No changes were made.

4. Now, start preserving your leaves. Remember to leave your first leaf unaltered. This is the control. The control has no alterations so you can compare your other preservation methods to the leaf with no changes.  The substance you use for preservation is your variable. Coat your second leaf with PVA glue, cover your third leaf with clear tape, and carefully paint your fourth leaf with clear nail polish. Make sure you cover the full surface on both sides of your leaves with your preservation materials. Remember, what you use to preserve your fifth and sixth leaves is up to you! (If you want to try even more preservation techniques for your leaves, check out these methods and see what works best!
http://www.hometrainingtools.com/a/preserving-autumn-leaves)

​5. Once leaves 2-6 are coated with their preservation materials, you must wait! Place the leaves with their labels on a surface where they won’t be disturbed, and check back each day for five days to record your observations.

6. When you check on your leaves, record your observations in your chart. What do they look like? Feel like? What techniques seem to be working? Which ones are not working as well? 

7. On day five, make your final observations. Rank the preservation techniques in order from best to worst. 

Extensions: 

Now that you know which technique works the best, go out and find more leaves to preserve! You can do all sorts of activities with your preserved leaves. Make a leaf book, leaf people, or leaf art! 

Google leaf people, leaf projects, or leaf art for all kinds of fun ideas! 

If you want to check out another fun leaf experiment, check out our blog on leaf chromatography: 

​http://discoveryexpress.weebly.com/blog/is-a-black-marker-really-just-black-is-a-green-leaf-really-only-green-these-are-the-questions-well-answer-today-using-chromatography


Image and Video Credits, in order of appearance: 

KentuckyKevin, 2014. Fiery autumn color 11-7-2014. Image uploaded from Wikimedia Commons on 10/14/2016.
https://upload.wikimedia.org/wikipedia/commons/5/58/Fiery_Autumn_Color_11-7-2014.JPG File used in accordance with the Creative Commons Attribution-Share Alike 4.0 International license. No changes were made. ​

References
http://www.science-sparks.com/2015/10/14/preserving-autumn-leaves/

Author: Maddie Van Beek

Halloween is only a few weeks away! That means it's time for some spooky fun with Halloween science activities! 


1. Use your colorful candy to try out candy chromatography! 


What exactly is chromatography? 


Chroma means color and graphein means to write. 


There are a few different kinds of chromatography, but today you are going to be dealing with paper chromatography. When you use paper chromatography, you can separate different inks or dyes into their individual components. For example, a black marker actually has many different colors of dye to create black ink.

​Watch the video below to watch how paper chromatography can be used to separate black ink into its individual colors:

You can use this same idea to separate the dyes of your favorite candies! 


YOU WILL NEED

• M&Ms or Skittles
• Coffee filter paper
• A tall glass 
• Water 
• Table salt 
• Pencil
• Scissors
• Ruler 
• 6 toothpicks 
• Aluminum foil 
• 2 liter bottle with cap

Check out our blog about candy chromatography here for instructions:

2. Create your own glowing beverages! 


Did you know that tonic water glows under a black light? The reason that it does this is because of one special ingredient: quinine. 


Why is quinine fluorescent? Read the link below to find out! ​

Now that you know about quinine, do you know what a black light is? Why is a black light any different from a regular light? They might appear the same as any other light bulb, but they function very differently. Black lights actually produce ultraviolet light. When you turn a black light on, it causes white things to glow in the dark. 


Read about black lights in the link below to find out how they work: ​

YOU WILL NEED

• Tonic water
• Ice cube trays
• Sprite or 7-up
• A black light

​
Here’s what to do! 


The instructions for this activity are very simple. Make ice cubes out of tonic water and then put them in any light colored drink such as 7-up or Sprite. Turn on a black light, turn off the lights, and watch your beverages glow an eery blue!

​
3. Make pumpkin slime!


The slime that you will be creating is a non-newtonian fluid. Newtonian fluids behave as you would expect a liquid to behave. For example, when you hit water, it gives way. You can easily put your hand through it without much resistance. Non-newtonian fluids sometimes act like a solid and sometimes act like a liquid. When you hit a non-newtonian fluid, it resists the impact. How can that be? 


Watch this video to see people experiment with non-newtonian fluid. They even try to bike across it! You’ll be amazed at its power to resist stress. 

YOU WILL NEED:

• One pumpkin
• Cornstarch 
• Mixing bowl
• Spoon
• Cookie sheet or pan
• Food coloring (optional: your pumpkin will already color your slime an orangey tint)

Check out our blog from a few weeks ago to learn more about non-newtonian fluids and create your own pumpkin slime:

References:
https://sciencebob.com/free-halloween-science-ideas/

http://www.scientificamerican.com/article/shining-science-explore-glow-in-the-dark-water/
​
http://science.howstuffworks.com/innovation/everyday-innovations/black-light.htm

Image and video credits, in order of appearance: 

Amos, E., 2010. Plain-M&Ms-Pile. File uploaded from Wikimedia Commons on 10/9/2016.
https://upload.wikimedia.org/wikipedia/commons/thumb/e/e5/Plain-M%26Ms-Pile.jpg/800px-Plain-M%26Ms-Pile.jpg Image released into the Public Domain. 

Pauller, N., 2014. Paper chromatography - Chemistry experiment with Mr Pauller. Video uploaded from YouTube on 10/9/2016. ​https://youtu.be/ZCzgQXGz9Tg

Hard Science, 2013. Biking across a pool of corn starch - Hard science. Video uploaded from YouTube on 10/9/2016. ​https://www.youtube.com/watch?v=BleCJJAKkgw&feature=youtu.be

Author: Maddie Van Beek

It’s October--the leaves are changing colors, the weather is getting cooler, and you are probably starting to see all kinds of gourds and pumpkins at the grocery store. These days, people seem to like pumpkin flavored ANYTHING. Today, we aren’t going to eat any pumpkin, but we ARE going to use a pumpkin in our science activity to create PUMPKIN SLIME!

Last year, we showed you how to create two different kinds of slime. If you missed it, check it out here: http://discoveryexpress.weebly.com/homeblog/two-times-the-slime-fun-with-polymers

When we create pumpkin slime, we are going to follow similar instructions for the first version of slime that we concocted. In this version, the special ingredient for creating slime is cornstarch. 

The slime that you will be making is called a non-newtonian fluid. Newtonian fluids, such as water, do not provide much resistance when stress is applied to them. If you jump in a pool, the water gives way. Non-newtonian fluids change their viscosity or “flow behavior,” when stress or pressure is applied to them. Simply put, this means that the slime acts like both a liquid and a solid. When you poke it or pick it up and roll it into a ball, it feels like a solid. When you stop playing with it, it runs through your fingers like a liquid. Can you think of other substances that might sometimes act like a liquid and sometimes like a solid? 

Check out this video about non-newtonian fluids to see them in action!

Here’s more information about non-newtonian fluids: http://sciencelearn.org.nz/Science-Stories/Strange-Liquids/Non-Newtonian-fluids

According to the link you just read, what other substances besides slime or “oobleck” are non-newtonian fluids? Can you think of any others?

Now that you know a little bit about the science behind the slime, let’s get started!

YOU WILL NEED:

• One pumpkin
• Cornstarch 
• Mixing bowl
• Spoon
• Cookie sheet or pan
• Food coloring (optional: your pumpkin will already color your slime an orangey tint)

Here’s what to do!

1. Cut the pumpkin in half and clean out the guts and seeds with your hands or a spoon. Put all the pumpkin innards into a mixing bowl. How do the guts feel? Look? Write down your observations.

2. Pour 1/2 cup of water into the mixing bowl and use the spoon to stir the water into the pumpkin guts. Write down your observations. How does adding water to the pumpkin change it? 

3. Measure 1 cup of cornstarch and pour it into the bowl with the pumpkin guts and mix with the spoon until well-blended. What does your mixture look like now? How has the consistency changed? Record your observations. 

4. Optional: add about six drops of food coloring and stir it in. 

5. Place the pumpkin half on a pan or cookie sheet with the hollow part facing upward (The pan is just to keep your play area clean).

6. Now that you have your pumpkin slime all ready to go, dump it back in the pumpkin half for goopy fall play! 

7. Have fun! Pick up your pumpkin slime and play with it! What does it feel like? Look like? Is this what you expected to happen? 


Extension: Try adjusting the amount of water, glue, or starch to see how it changes the quality of the slime.




References:

http://littlebinsforlittlehands.com/pumpkin-oobleck-science-sensory-play/

https://sciencebob.com/make-some-starch-slime-today/

https://sciencebob.com/make-some-starch-slime-today-method-2/

http://serc.carleton.edu/sp/mnstep/activities/35866.html

http://scifun.chem.wisc.edu/homeexpts/gluep.htm

https://en.wikipedia.org/wiki/Non-Newtonian_fluid

Image and video credits, in order of appearance: 

Moore, K.T., 2015. Silverman's Farm. File uploaded from Wikimedia Commons on 10/3/2016. 
https://upload.wikimedia.org/wikipedia/commons/thumb/a/a1/Silverman%27s_Farm.jpg/800px-Silverman%27s_Farm.jpg File used in accordance with the Creative Commons Attribution-Share Alike 4.0 International license. No changes were made.

The Discovery Slow Down, 2013. Non-Newtonian Liquid IN SLOW MOTION! Video uploaded from YouTube on 10/3/2016. https://youtu.be/G1Op_1yG6lQ

2009. Pumpkin2007. File uploaded from Wikimedia Commons on 10/3/2016. 
https://upload.wikimedia.org/wikipedia/en/d/d8/Pumpkin2007.jpg File released into Public Domain. 

BradBeattie, 2006. Pumpkin seeds in hand. File uploaded from Wikimedia Commons on 10/3/2016. 
https://upload.wikimedia.org/wikipedia/commons/thumb/e/e8/Pumpkin_seeds_in_hand.jpg/800px-Pumpkin_seeds_in_hand.jpg File used in accordance with the Creative Commons Attribution-Share Alike 3.0 Unported license. No changes were made.

​

Author: Maddie Van Beek

It’s officially fall! Thursday, September 22nd marked day one of a new season, and you may have already felt it in the weather. Fargo has been characteristically chilly this past weekend! With the fall season comes new colors in your surroundings. You’ll notice once-green, lush plants either dry out and turn brown, OR as they dry, they may transform into a vibrant yellow, red, or orange! How do you know what color the leaves will change? There’s actually a way to find out, and that’s what we will learn about today! Before we get going on our activity, let’s learn more about why leaves change color in the first place. 


Why are leaves green? Chlorophyll is a chemical in plants that helps photosynthesis occur. Photosynthesis is the process in which plants are able to absorb water and carbon dioxide and turn it into food. This could not happen without the help of sunlight! 


Here is a diagram of how photosynthesis occurs: ​

YOU SHOULD KNOW:

• What makes leaves green? 
• Describe what photosynthesis does? 
• What do leaves need for photosynthesis to occur? 
• What purpose does chlorophyll serve? 
• How do leaves change color? 

Now that you know the science behind the beautiful fall scenery, let’s move on to our activity! Your job is to determine the future colors of the leaves. Let’s get started! 
 
YOU WILL NEED:

• Fresh, green leaves (make sure they haven’t begun to change color and aren’t crunchy)
• Bowl
• Hot water
• Rubbing alcohol
• Coffee filter
• Scissors
• Clear glass or jar
• Plastic wrap
• Spoon or fork

Here’s what to do! 

1. Gather some fresh green leaves from your yard or somewhere outside. Make sure the leaves are all green. Your leaves should NOT be dry or crunchy. 
2. Bring your leaves inside and rip them into tiny pieces. 
3. Put the leaf pieces into the clear glass or jar. Pour rubbing alcohol over the leaf shreds until they are completely covered. 
4. Use a spoon or fork to mash the leaf bits up and stir them in with the rubbing alcohol. You may see the rubbing alcohol begin to turn green. 
5. Place plastic wrap over the mouth of the jar and secure it. 
6. Heat up a bowl of hot water. Carefully place the jar in the center of the bowl. The level of the hot water should be just above the level of the rubbing alcohol. 
7. Leave the jar in the bowl of hot water for at least 30 minutes. Swish the jar around every once in a while the stir up the leaves. You should notice the rubbing alcohol turning a very dark green. 
8. After 30-60min, you should be ready to move on! Cut a strip of coffee filter (or paper towel) so you have a long rectangle. 
9. Dangle the coffee filter strip into the jar of rubbing alcohol so one end of the strip is touching the surface of the rubbing alcohol and the other end rests over the edge of the jar. 
10. Now, just wait patiently. The rubbing alcohol will travel up the coffee filter strip and carry the green pigment with it. As the rubbing alcohol travels upwards, the once all-green pigment will separate into more than one color. You’ll see green (the chlorophyll) and another color such as yellow, orange, or red appear. 
11. Gather leaves from other types of trees and repeat the process to see if you can get other colors to appear! 

Image and video credits, in order of appearance:


Jongleur100, 2007. Country lane. File uploaded from Wikimedia Commons on 9/25/2016. https://upload.wikimedia.org/wikipedia/commons/thumb/1/18/Country_lane.jpg/800px-Country_lane.jpg File in the Public Domain. 

At09kg, 2011. Photosynthesis. Uploaded from Wikimedia Commons on 9/25/2016.
https://upload.wikimedia.org/wikipedia/commons/thumb/d/db/Photosynthesis.gif/800px-Photosynthesis.gif
File used in accordance with the Creative Commons Attribution-Share Alike 3.0 Unported license. No changes were made. 
​

References
https://en.wikipedia.org/wiki/Autumn_leaf_color
https://en.wikipedia.org/wiki/Chlorophyll
https://en.wikipedia.org/wiki/Photosynthesis
http://www.howweelearn.com/science-experiments-for-kids/

Author: Maddie Van Beek 

You may have heard of yeast, but today you will actually learn what this substance is and what it does.

​Have you ever seen a little square packet labeled yeast in your cupboard at home or on a shelf at the grocery store and wondered it was used for? 

Inside the packet, you’ll see a substance that looks something like this:

Pretty boring, right? Why would these little brown granules called yeast be so important for making bread? 

Did you know that yeast is not only crucial to bread rising, it is actually ALIVE?!

The scientific name for this tiny little organism is Saccharomyces cerevisiae, but they should just call it, “sugar-eater.” Yeast feeds on the sugar in the bread dough and converts it into carbon dioxide. The carbon dioxide creates little bubbles in the dough, which is what causes the bread to rise and creates a nice spongy texture rather than a hard flatbread. Your PB&J sandwiches would have never been the same without the discovery of yeast! 

This could not happen without yeast:

Here is a close-up of what yeast organisms look like:

CHECK FOR UNDERSTANDING:

• What kind of organism is yeast? 
• Where might you find yeast?
• What does yeast do? (What is its job?)
• What is yeast used for? Think of a few different examples. 

Learn more about bread-related science and the research that is going into yeast today!

Remember when we blew up a bag with baking soda and vinegar? Today, we are going to try something similar with yeast!

Check out this video for a demonstration of what you will do!

CHECK FOR UNDERSTANDING:

• Based on your experience last week, what do you think is happening as the yeast blows up the balloon? 
• How is the balloon being blown up?
• What is the yeast doing to produce gas?
• What kind of gas is being produced? 

Now that you've seen a demonstration of what yeast can do, try it out yourself! 

YOU WILL NEED:

• Baker’s yeast
• Warm water
• Water bottle
• Balloon
• Sugar
• Funnel

HERE’S WHAT TO DO:

1. First, you need to stretch out your balloon. Blow it up a few times to loosen it up. 
2. Next, measure one cup of very warm water.
3. Stir in one packet of yeast and two tablespoons of sugar. Keep stirring until the mixture is dissolved.
4. Place the funnel at the mouth of the water bottle, and pour the sugar-water-yeast substance into it. 
5. Stretch the mouth of the balloon over the mouth of the water bottle.
6. Wait, and record your observations. This may take a while, so you might want to check back every 15-20 minutes. 
7. What does the sugar-water-yeast substance look like at first? What happens over time? What happens to the balloon? How long does this take? 

Extension 1:

Test out how different water temperatures might affect the yeast! 




YOU WILL NEED:

• Thermometer
• Ruler/tape measure

PREDICT: How might temperature affect the yeast? 




HERE’S WHAT TO DO:

1. Follow the instructions above, except use a different temperature of water. Try using very hot water, lukewarm water, cold water, etc. You will need a thermometer in order to accurately track how temperature affects the production of carbon dioxide. 
2. Use a ruler to measure how large the balloon gets. Measure from the mouth of the water bottle to the top of the balloon each time.  
3. Repeat the experiment as many times as you would like with different temperatures of water and record your observations each time. 
4. Create a graph to demonstrate the relationship between water temperature and carbon dioxide production. Your X-axis would be temperature and your Y-axis would be inches grown. For Excel instructions, check out our recent blog on heart health. (You would be creating a graph of inches  grown as a function of water temperature). 

Extension 2:

Test out how different amounts of sugar might affect the yeast!

Does more sugar equal more carbon dioxide? Try it out! 

PREDICT: How might the amount of sugar affect the yeast? Will more sugar make the balloon grow bigger? 


HERE'S WHAT TO DO: 

1. Follow the instructions in the original experiment, except use a different amount of sugar. Try using one tablespoon, 1/2 teaspoon, 1/4 cup, etc. 
2. Use the ruler to measure how large the balloon gets. 
3. Create a graph to demonstrate the relationship between the amount of sugar used and carbon dioxide production. Your X-axis would be the amount of sugar used and your Y-axis would be inches grown. For Excel instructions, check out our recent blog on heart health. (You would be creating a graph of inches grown as a function of the amount of sugar used). 

References: 

http://phys.org/news/2013-11-bread-beer-national-yeast-cultures.html

http://www.scientificamerican.com/article/watch-yeast-live-breathe/

https://www.exploratorium.edu/cooking/bread/activity-yeast.html

http://science.howstuffworks.com/life/fungi/yeast-info.htm

http://en.wikipedia.org/wiki/Yeast#Baking

Image and video credits, in order of appearance
​
Hellahulla, 2007. Compressed fresh yeast. Uploaded from Wikimedia Commons on 9/11/2016.
https://upload.wikimedia.org/wikipedia/commons/thumb/e/e9/Compressed_fresh_yeast_-_1.jpg/1024px-Compressed_fresh_yeast_-_1.jpg File used under GNU Free Documentation License. No changes were made. 

Ranveig, 2005. Dry yeast. 
​https://upload.wikimedia.org/wikipedia/commons/thumb/9/90/Dry_yeast.jpg/800px-Dry_yeast.jpg File in the Public Domain. No changes were made. 

Reynaud, 2012. Bread rising (Timelapse). Uploaded from YouTube on 9/11/2016. 
​https://youtu.be/0z8hrRXQuHY

Masur, 2009. S cerevisiae under DIC microscopy. Uploaded from Wikimedia Commons on 9/11/2016. https://upload.wikimedia.org/wikipedia/commons/thumb/d/d9/S_cerevisiae_under_DIC_microscopy.jpg/800px-S_cerevisiae_under_DIC_microscopy.jpg File in the Public Domain. No changes were made. 

Timstar Laboratory Suppliers, 2013. Demonstration of keystage 3 biology experiment - Blow up a balloon with yeast. Uploaded from YouTube on 9/11/2016. ​https://youtu.be/wTmcUvQhU-o