With summertime here, kids will be spending more time in parks, backyards and at cabins. Pressing plants to make a botanical collection and nature journaling get them outdoors to interact with the environment and discover the science all around them. Here’s a short video demonstrating how to press plants using cardboard, newspaper, watercolor (absorbent) paper and a heavy book.
(Project from The Kitchen Pantry Scientist, Biology for Kids Quarto Books, 2021)
From surface tension to evaporation, science come into play every time you blow a bubble. Here’s some bubble science, along with a recipe for making giant bubbles from my book Outdoor Science Lab for Kids!
Water molecules like to stick to each other , and scientists call this sticky, elastic tendency “surface tension.” Soap molecules, have a hydrophobic (water-hating) end and (hydrophilic) a water-loving end and can lower the surface tension of water. When you blow a bubble, you create a thin film of water molecules sandwiched between two layers of soap molecules, with their water-loving ends pointing toward the water, and their water-hating ends pointing out into the air.
As you might guess, the air pressure inside the elastic soapy sandwich layers of a bubble is slightly higher than the air pressure outside the bubble. Bubbles strive to be round, since the forces of surface tension rearrange their molecular structure to make them have the least amount of surface area possible, and of all three dimensional shapes, a sphere has the lowest surface area. Other forces, like your moving breath or a breeze can affect the shape of bubbles as well.
The thickness of the water/soap molecule is always changing slightly as the water layer evaporates, and light is hitting the soap layers from many angles, causing light waves to bounce around and interfere with each other, giving the bubble a multitude of colors.
Try making these giant bubbles at home this summer! They’re a blast! (It works best a day when it’s not too windy, and bubbles love humid days!)
To make your own giant bubble wand, you’ll need:
-Around 54 inches of cotton kitchen twine
-two sticks 1-3 feet long
-a metal washer
1. Tie string to the end of one stick.
2. Put a washer on the string and tie it to the end of the other stick so the washer is hanging in-between on around 36 inches of string. (See photo.) Tie remaining 18 inches of string to the end of the first stick. See photo!
For the bubbles:
-6 cups distilled or purified water
-1/2 cup cornstarch
-1 Tbs. baking powder
-1 Tbs. glycerine (Optional. Available at most pharmacies.)
-1/2 cup blue Dawn. The type of detergent can literally make or break your giant bubbles. Dawn Ultra (not concentrated) or Dawn Pro are highly recommended. We used Dawn Ultra, which is available at Target.
1. Mix water and cornstarch. Add remaining ingredients and mix well without whipping up tiny bubbles. Use immediately, or stir again and use after an hour or so.
2. With the two sticks parallel and together, dip bubble wand into mixture, immersing all the string completely.
3. Pull the string up out of the bubble mix and pull them apart slowly so that you form a string triangle with bubble in the middle.
4. Move the wands or blow bubbles with your breath. You can “close” the bubbles by moving the sticks together to close the gap between strings.
What else could you try?
-Make another wand with longer or shorter string. How does it affect your bubbles?
-Try different recipes to see if you can improve the bubbles. Do other dish soaps work as well?
-Can you add scent to the bubbles, like vanilla or peppermint, or will it interfere with the surface tension?
-Can you figure out how to make a bubble inside another bubble?
Summer is almost here, and so are the bugs! Here’s a short video segment featuring two inspiring scientists, paired with fun projects from my new book, “Biology for Kids” (available everywhere books are sold.)
Made corn starch frescoes from my book “Outdoor Science Lab for Kids” on @fox9morning today! Mix 2 parts cornstarch with 1 part water, pour out on baking sheet or sidewalk and paint with watercolors or food coloring! (Wear old clothes if painting with food coloring) Let frescoes dry, or wash away with a garden hose.
Take your summer food game up a notch using… science! Sorbet recipe below. Vinaigrette recipe is in the post below this one.
Simple Freezer Strawberry Sorbet (adapted from Epicurious.com)
30 minutes hands-on prep time, 8 hours start to finish
*Parental supervision required for boiling sugar syrup
a shallow dish
1 quart strawberries
1/3 cup lemon juice
1/3 cup orange juice
1 cup sugar
2 cups water
What to do:
- Make a sugar syrup by bringing 1 cup sugar and 2 cups water to a boil in a heavy sauce pan. Boil for 5 minutes.
- Puree strawberries in a blender or food processor until smooth.
- Add strawberries, lemon juice and orange juice to the sugar syrup.
- Pour mixture into a shallow dish and cool for 2 hours in the refrigerator.
- Put the chilled sorbet mix in the freezer for 6 hours, stirring every hour.
- Enjoy your sorbet!
The Science Behind the Fun:
In sorbet, sugar acts as an antifreeze agent, physically getting in the way of ice crystal formation to keep crystals small, so that you don’t end up with one big chunk of ice. Pre-chilling the mixture before freezing it allows it to freeze faster, which also encourages smaller crystals to form.
Looking for fun, creative summer projects? I showed off some projects from STEAM Lab for Kids this morning on WCCO MidMorning!
It’s almost summer! Whether you’re heading to the back yard, a park or a nature center, here are a few of our favorite free apps to enhance your next outdoor adventure…
Merlin Bird ID (free) The Cornell Lab of Ornithology makes it easy to identify that mystery bird in your back yard. http://merlin.allaboutbirds.org/
Leaf Snap: (free) Take a photo, identify a plant.http://leafsnap.com/
Bee Friendly: (free) Be a citizen scientist with this cool app that lets you identify and tracking pollinators like bees in your area. http://earthwatch.org/scientific-research/special-initiatives/bee-friend-your-garden
Starmap: iOS (Starmap Lite is free.) Use this app to easily find and identify constellations in the night sky. http://www.star-map.fr/
ISS Spotter: (free) It’s cool to watch the International Space Station fly across the horizon at night. This app will help you spot it, and even has an alarm so you don’t miss it. https://itunes.apple.com/us/app/iss-spotter/id523486350?mt=8
Magnificent : (free version) Magnify leaves, bugs and anything else you want to take a closer look at. http://habitualdigitalsoftware.com/
Between working on a follow-up to Kitchen Science Lab for Kids (which involves testing, writing up and photographing 52 experiments), driving my kids around to camps and sports, and doing science outreach at libraries, bookstores and on TV, I’m finding it hard to keep up. Here’s a short video on how to make tie-dye milk (a surface tension experiment), which I did on WCCO Mid Morning show last week and forgot to post!
Luckily, between all the camps and activities, the kids and I are having fun digging in the dirt, blowing giant bubbles, and watching tadpoles and monarch caterpillars go through metamorphosis!
What science experiments are you doing this summer? It’s a great time to take science outdoors!
Here are some of our favorites:
Hungry? Build a solar oven from a pizza box and bake s’mores.
Stand on eggs or throw them as hard as you can without breaking them. You can always clean up mistakes with your hose!
And no summer would be complete at our house without an epic marshmallow shooting competition. You’ll even learn some physics!
Too hot to bike? Pool too crowed? Try some hot weather science! Just find a shady spot in the driveway, pull out the garden hose and you can experiment with:
and fire-proof water balloons.
Click on the experiment names to read directions and learn more about the science. Have fun!
This week, abulleyeview.com featured three of my favorite summer science experiments and I showed Twin Cities Live viewers how to make nature walk bracelets and green slime! (Oh yeah, we also broke a few eggs.)
What summer science experiments have you tried?
Don’t forget to download KidScience app for more great ideas! We just added a new experiment and have another one on the way!