Wednesday Explorers Club ~ Scavenger Hunt

The season is tilting away from winter, but there's plenty of "winter" stuff to see outside. So head out on a scavenger hunt - but instead of collecting things, you'll be observing them, taking photos or drawing them, looking closer.... getting to know the winter-ish plants and animals around you.

Things to take on your hike:
a hand lens
a sketchbook and pencils
camera

Scavenger hunt list of things to look for and observe:

• icicle or frozen puddle
• cluster of needles
• a pine cone
• winter weeds
• animal tracks (what are they and where do they lead?) 
• clouds
• birds flying
• berries
• a nest (don't touch)
• dead leaves clinging to a tree
• snowfleas at the base of trees
• a cocoon on a twig or side of house, or beneath leaves

Wednesday Explorers Club ~ freezing soap bubbles

Frozen bubble (CC use by Max Pixel)

Can you freeze a bubble? Sure. All you need is some heavy-duty winter-weather bubble mix and a wand or large straw. And a day when the temperatures dip below freezing. Here's one recipe for bubble mix:

• 3 cups water
• 1 cup liquid dish-washing detergent
• 1/2 cup white corn syrup

Adding corn syrup to the soap bubble recipe creates a sugar polymer and a stronger bubble that can survive freezing temperatures.

Head out and try blowing bubbles. Sometimes they will freeze in the air. If that doesn't work, coat a porch railing with a bit of soap solution and then blow a bubble on top of that. Or blow a bubble and attach it to pine needles or winter weeds.


As the bubbles freeze, it looks like bits of frost or snowflakes are forming and growing. What's happening is that the soap bubble is made up of three layers: a thin layer of water molecules squished between two layers of soap. The water layer freezes first, and at lower temperatures than the soap layer.

More Things to Do

• Make bubbles using bubble mix that has been cooled in a refrigerator for 15 minutes or so, and compare with bubbles made using room-temperature mix.
• Try adding sugar to some mix. Does it help bubbles form faster?
• Poke a frozen bubble. What happens? 
• Try to take photos or videos of your bubbles
• Compare bubbles made with a straw versus those made with a wand.
• What happens if you put a drop of food coloring in the mix?
• Try capturing a bubble and putting it in the freezer

If you live where it is warm: blow a bubble on a plastic plate or jar lid and put it in the freezer. What happens?

Wild Outdoor Wednesday

 Look for homes in trees: nests, cavities, cocoons, and chrysalises. Record your observations in images, colors, and words

Remember to take your sketchbook or journal with unlined pages, something to draw and write with, and something to add color ~ watercolors, colored pencils, crayons, or markers.

Squirrel Studies Beneath the Birdfeeder

Squirrels are pretty smart. Not only can they figure out the best route to your birdfeeder, but they remember where they’ve hidden nuts.

You don’t need to build a maze to test your backyard squirrels’ IQ, but you do need to think like a squirrel. For example, which is better: a big nut or a little nut? To find out, create a “squirrel feeding area” and offer your neighborhood squirrels their choice of peanuts of walnuts. Put ten of each out and count how many are left after each squirrel visit. Then replace so you have 10 of each.

Can squirrels associate food with a specific container? Since squirrels can see color, you might offer peanuts in a white cup and filberts in a black cup. Do they show a preference for one container over another? If they do, what happens when you put the nuts in the wrong container?

Squirrels can open a box and figure out how to get in vending machines, but can they learn how to open a plastic jar? If you have a large wide-mouthed plastic jar, put peanuts inside it and leave the lid off. Let the squirrels learn to associate the jar with food. Then put the lid on, but not very tight. Do your squirrels figure out how to turn the lid? Let me know if they do, because my squirrels got frustrated and bit the lid off my jar.

 

Check out other science resources and book reviews at the STEM Friday blog.

Who's at Your Feeder?

Every winter we hang a bird feeder from the clothesline. We fill it with sunflower seeds and millet and thistle... a whole mix of nutritious seeds for the local flocks. We also hang suet for the woodpeckers - then we watch from the living room window.

Here's who visits our feeder:
chickadees
nuthatches
juncos
blue jays
downy woodpeckers
hairy woodpeckers
red-bellied woodpeckers
mourning doves (they pick up seeds that fall)
goldfinches, cardinals, sparrows, turkeys and squirrels. Lots of squirrels.

Gray Squirrels who climb up the tree, clamber out onto a limb, leap onto the clothesline and tightrope walk to the feeder. They chew the suet. They scoop out seeds by the pawful, tossing them to bird and mammal below.

We wondered if giving the squirrels their own food would keep them from raiding the birdfeeder. So one day I lugged home ten pounds of unsalted peanuts in the shell. We put some outside on the chopping block. We tossed a handful beneath the feeder. We watched and waited. What we discovered: blue jays love peanuts! If the squirrels are too slow, the jays swoop in and try to make off with peanuts in their beaks. They fly around the house to the thicket of forsythia and lilac where they sit around their card table, playing poker and cracking the nuts.

What backyard wildlife visits your feeder? Check out other science resources and book reviews at the STEM Friday blog.

Ice Watching

We get a lot of ice here in upstate New York... different kinds of ice, depending on the season. Early on, when the cold is a novelty, we like to crunch through the thin frozen ice skins covering puddles. Later, we like to look at things caught in the ice; frozen just beneath the surface.

According to Ellen Obed, there are Twelve Kinds of Ice, each with its own season. Why not spend a few days this winter checking out the kinds of ice you have in your backyard? Is it thick or thin? Is it smooth or bumpy? How many kinds of ice do you have over a winter?

Does your ice sing?

Try tapping on ice with your fingers, a stick, or a spoon. What do you hear? Does thick ice sound different than thin ice? How else can you use ice to make music? Check out how these Siberian drummers make music with the ice on Lake Baikal. The lake is thousands of feet deep, but this section - with the musical ice - is rather shallow... about 5 feet deep.

http://youtu.be/en0p1Y35p3w

Getting Traction on a Slippery Surface
If you have a battery-powered toy car, try running it across your icy patch. What sorts of things might you use to help its tires get a grip? Instead of tossing salt on the ice, try some natural things to see if they might help. For example: sand, ashes, tree bark mulch, clean kitty litter, grated beets. Check back during the day to see if any of these things help melt the ice.

The power of Freezing
If you've ever left a plastic bucket of water outside during the winter, you already know that the expansion of freezing water can leave a crack down the side of your bucket. That force of freezing water is one thing that helps break rocks apart. I wonder if it might be used to split those huge logs sitting by my woodpile?

Check out other science resources and book reviews at the STEM Friday blog.

No Icicles? Make your Own

Nothing says "winter" like icicles. Those are the frozen spikes that form when dripping water freezes.

If you don't have icicles (yet), and it's cold outside, you can make your own. All you need are:
some coffee cans (or #10 cans)
string
hammer and nail
thumbtack
food coloring

First you need to make something that holds water, but leaks: a can. Start by using the nail to punch three holes around the top rim of each can - evenly spaced. Tie a string through each hole and bring the ends together and tie them in a loop. That's so you can hang your icicle-makers from a tree branch away from sidewalks and driveways.

Then, use the thumbtack to make a hole in the bottom of each can. Make one hole as tiny as possible, and the others of various sizes. On a cold night, cold enough to freeze the water, take your cans outside and fill them half full with water. Add food coloring for tinted icicles. Then hang each icicle-making can on a branch and let it go to work.

In the morning, check on your icicles. Did the size of the hole in the bottom of the can make any difference in the size of your icicles? What happens to them during the day?

One thing you might notice about your icicles is that they all have a "carrot" shape. There's a reason for that, say scientists.As water drips onto an icicle and freezes, it releases heat. The warm air rises up the sides of the icicle and acts like a blanket, or insulator. The insulation is very thin at the tip, and thick at the top. So that's why the tip grows thin and rapidly, and the top grows slowly. Find out more about the math behind icicles here.

Snow Globe Science

photo by Sophia at Mamasaymamaso

I've got a snow globe that I love - and a magic wand full of glitter and tiny stars and moons. And one of the questions that I've been mulling over is: how do they get that glittery stuff to float so gently (instead of fall down fast)?

So I thought it might be fun to explore how things fall in liquid by experimenting with glitter globes - simple globes you can make at your dining room table.

What you need:

• a small glass jar with a tight lid (large baby food jar works well)
• 1 or more skinny jars for liquid testing (like spice jars)
• water
• mineral oil
• glycerin
• glitter (different kinds if you can find them)
• small plastic figures (old holiday ornaments work well)
• hot glue gun
• toothpick & dish soap
• pipe thread tape (to help seal jar lid if it leaks)
• measuring spoons
• optional: stopwatch for timing how fast glitter falls

How fast does glitter fall through different liquids?  
Fill your liquid-testing jar with water fill a  1/2 teaspoon with glitter. Before you add glitter to the water, dip a toothpick into some dish soap and touch it to the surface of the water. This will break the surface tension so the glitter won't glom all together on top. Then add the glitter and start timing.
Do the same thing with a testing jar filled with mineral oil.
Then try different mixes of water and mineral oil.
Try adding small amounts of glycerin (1/4 teaspoon at a time) to see whether that changes how fast your glitter falls.

Do some kinds of glitter fall faster than others?
Test different kinds of glitter with water to see how fast they fall. Use the same amount (1/2 teaspoon) for each type of glitter. Remember to use a toothpick dipped in dish soap to break the surface tension before you add the glitter.

Make a snow globe!
Glue a figure onto the lid of your baby food jar. When it's dry, add the liquid mix you like best, then add your glitter (remember the toothpick/dish soap trick). Put some pipe thread tape around the inside of the jar lid and screw it on. Now shake and enjoy.

 Today is STEM Friday - head over to the STEM Friday blog to see what other people are talking about in science.

Noisy Wings!

Sounds seem crisper in winter. If you listen, you can hear the hiss of icy pellets hitting the ground, the sharp calls of birds slicing through the air and - if you stand very close and very still - the flir-r-r of bird's wings as chickadees and juncos and nuthatches come in for a landing at the feeder.

What sounds do you hear when you head outside this week? Try making a sound map. All you need is a scrap of paper, a pencil, and a cup of hot cocoa to keep you warm...

Check out more STEM Friday resources here. And if you want help identifying some of those birds making lots of flirry wing noise at the feeder, download a poster of frequent feeder birds here.

Bugs & Bugsicles ~ Insects in Winter

Last week I wrote about the snow fleas hopping all over my ski tracks. Turns out lots of insects have similar strategies for dealing with winter weather.

Some go dormant, entering a state called “diapause”. That’s a state of dormancy that might look like hibernation but isn’t. It’s used as a way to survive temperature extremes, drought, or other unfavorable conditions. Insects that spend the winter in diapause can withstand a temperatures as low as 94 degrees below zero Fahrenheit (-70 C).

How do they do it? Some have antifreeze compounds that supercool their body fluids and tissues – sort of like ethylene glycol used in antifreeze for cars. Other insects freeze, turning into bugsicles – like the Arctic Woolly Bear caterpillar that Amy Hansen writes about in her book,

Bugs and Bugsicles.

Bugs and Bugsicles: Insects in the Winter

By Amy Hansen; illustrated by Robert C. Kray

32 pages, ages 7-9; Boyds Mills Press

In Bugs and Bugsicles, Hansen shows the diversity of strategies insects use to survive winter. Unlike the grasshopper of Aesop’s Fables fame, many insects begin their winter preparations while the weather is still warm. In late summer Monarch butterflies get ready to fly to Mexico, honeybees cap off their cells full of pollen and nectar, and ants stockpile seeds of all sorts and sizes.

Dragonfly nymphs curl up in the mud. Not only does the mud protect nymphs from cold, but it hides the nymphs from hungry fish. Ladybugs are more gregarious – they snuggle in hidden ladybug clusters until spring returns. And some insects go to sleep or, like the Arctic Woolly Bear, freeze until spring thaw.

Bug antifreeze works because, as the temperature drops, their cells produce glycerol (or other compounds). These compounds prevent water crystals from forming within the cells – and that’s important, because water freezes and any ice crystals would rupture the cells and  kill the insects.

Hansen includes some hands-on investigations for curious bug-ologists- but here’s one you can try. You’ll need 2 ice cube trays, a couple cups, a measuring cup, some sugar and a freezer (or a really cold day).

Mix 1/2 cup of sugar with 1 quart of water. Fill up an ice cube tray with this solution.

Put water in the other ice cube tray. Put both trays in the freezer and check after an hour.

You can read more about insects in winter here - and check out more science resources at STEM Friday! Review copy provided by publisher.