30 Second Christmas Science - Viewing Christmas Lights Through a Feather

For a quick, but colorful, Christmas, science demonstration, have children look at the lights on a Christmas tree through a feather (a craft feather will do).

It helps if the room is dim, and they might have to close one eye, but they should see a rainbow type spectrum of color, as the light from the tree is bent and diffracted, passing through the thin slits between the filaments of the feather.

The effect is not quite as dramatic as looking at the lights through a commercially produced diffraction grating...

...but it's still pretty.

For further exploration, have children look at different types, or even different colors of lights through their feathers.  Does the type of light change the type rainbow they see? 

Or, do a little research together into how this effect might relate to the beautiful colors of a peacock's feathers. 

Or, try out other diffraction gratings you might have sitting around the house.  The Exploratorium  website suggests a metal screen, two pencils held closely together, a piece of cloth, or even one strand of hair.  They also have a nice (almost child friendly) explanation of what is happening to the light.

Christmas Themed, Half Square Quilt Puzzle Patterns.

This weekend, we're spending cozy afternoons piecing our card stock, half square, triangle puzzle pieces into Christmas patterns:

Christmas trees...

...Santas...

...peppermint pinwheels...

...ornaments...

...and stars...

...or snowflakes...

...depending on their colors.

Homemade Christmas Gummy Bears

I was making up this year's batch of Christmas gummies, using the candy molds saved from last year's Advent calendars...

...and a half batch of our favorite gummy recipe from Not So Idle Hands -

Combine in a small saucepan:

1 3oz packet of flavored gelatin

3 packets of unflavored gelatin

1/3 cup + 2 tablespoons water

Leave the gelatin and water for about 10 minutes, or until all of the water has been absorbed.

Place over medium-low heat, stirring constantly, just until the gelatin has melted.  Do not allow it start cooking.

Pour immediately into molds.

This year, I discovered Jolly Rancher Jello.  I didn't even bother to check the sugar content, because I'm sure it's ridiculously high, but Wow!  It makes for fantastically good gummy candy.

Anyway, while I was busy pouring the gummy into molds, it occurred to me, that if the Lego candies could have a Christmas make-over (see yesterday's post for that), then our giant gummy bears could too. 

So, I set the Advent calendar molds aside, dug out our bear pans (non-affiliate link), and poured a second set of half batches of melted candy into squeeze bottles (the ones we used for making gummy creations)...

...to make it easier for filling in details, like the bow ties, in one color...

...before filling the pan with another.

A few minutes in the fridge, and the bears were ready to pull right out of the pans.

The half batch of the gummy recipe (or the entire amount listed at the top of this post) is enough to fill one bear pan completely, for a nice thick bear, or two pans halfway, for thinner bears.

Oh, and you need to let the bow ties, or other details, set up for a few minutes in the fridge or freezer, before pouring in the rest of the gelatin, which should have cooled just a little by then too.  Otherwise the bow ties will run, or be completely absorbed into the new color. 

If the gelatin cools too much for pouring, you can remelt it, by holding the squeeze bottle down in a cup or pan of hot water.

Allow the gummies to set out for a few hours, to dry to whatever texture you like, and then store them in an airtight container.  I imagine they'd be good for a few days, but honestly ours are pretty much always all devoured before they finish drying, so I can't say for sure.

Lego Candy Carolers

There's always one guy who just won't sing.

Merry Christmas.

Fractal Christmas Tree Paper Craft

I saw one last Christmas themed fractal, as I was sorting through Google images, that I thought would be perfect to turn into a paper, cut and glue, craft for the children.  If you do an Internet search for "Christmas fractals" you'll find an amazing assortment of mesmerizing images, as well as a few of these simple little trees.

We worked on our tree as a group.

D (age 11) made the base (a Sierpinski carpet)  by trimming a sheet of brown construction paper into a square...

...then cutting that square into 9 smaller squares, and removing the center square...

...and cutting the remaining squares into 9 smaller squares...

...and removing the center squares.  Normally we would have left the large square intact, and cut the middle squares out with a pen knife, or razor blade.  Unfortunately, since our move, I haven't been able to locate any of our pen knives, so we just cut the squares apart with scissors, and taped them back into place around the omitted squares.

When the squares got too small for cutting and taping, D switched to coloring in the middle squares, to represent a blank section.

While he worked on that, A (age 13) joined the younger children (after abandoning the fractal snowflake puzzle project that was going on, at the same time, in the basement), in cutting 9 sheets of green construction paper into large equilateral triangles, to be cut apart again, and again, each time removing the center triangle, in preparation for the Sierpinski triangle branches.

Being a middle schooler, I decided to have her cut the triangles one time more than I would have had the younger children cut.  Which, made for enough measuring and cutting of triangles, that the snowflake project was beginning to look better and better to her, but also made for a prettier pattern in the end.

While, their older siblings were measuring and cutting, I gave the younger girls (ages 8 and 10) a sheet of Apollonian gaskets (you can find printable images of them on many different sites), to color in...

...as Christmas ornaments.

I pieced the tree together, incorrectly at first (all those triangles were going to my head)...

...and the younger girls traced, cut out, and pieced together two more equilateral triangles to form the second iteration of the Koch snowflake - or in other words, a star, for the top of the tree.

We decided there were too many triangles to tape back together, and that it would be better to glue them down to a sheet of paper, instead.  After looking around the house for sheets large enough to fit behind the tree (we needed something about 4'x4'), we settled on one of the plastic tablecloths we had used under our toothpick and marshmallow star.

I think a red, or yellow background would have been even better, but we had green (left over from a Lego Friends birthday party) and so it had to do.

After the glue dried, we cut the excess tablecloth away...

...and hung the tree as a replacement for the grid art turkey we'd hung on the wall before Thanksgiving (again, down in the dark, photograph hating basement)...

...where it appears much brighter, and more mathematically festive, in real life.

Craft Stick Snowflake Puzzle - A Little More Fun With Fractals

We've been playing around a lot with fractals this week, partly because so many of them happen to look Christmasy, and partly because they make for a good break from our usual math lessons while still keeping us on our toes. 

One of the things I really like about fractals, apart from the mind blowing detail of their representing infinity in a finite space, is the simplicity of  their design.  Take the Koch snowflake for instance, iteration after iteration the pattern appears more and more complicated, ultimately creating a ridiculously intricate design.  But, on closer inspection, the entire figure is made up of one simple pattern, repeated over and over again.

Repeat the pattern three times...

...and you can put it together to form a star (the 2nd iteration of the Koch snowflake).

Repeat it 48 times, and you can puzzle out the 4th iteration snowflake (assuming of course you have a fair amount of free floorspace and plenty of popsicle sticks).

We have a good deal of floor space in our basement family room (just terrible lighting for picture taking), and I had a couple of teens to keep busy, while I crafted with their younger siblings, so puzzling out a snowflake seemed like a perfect project for them.

Puzzling is the right word too, because even though the snowflake looks like a six sided shape, it's really just a triangle.  Keeping that fact (and the sides) straight is quite a brain teaser.  The girls used a protractor to check their angles (all the points form the 60° angles of an equilateral triangle)...

...and double checked their completed project (a solid hour of worth of work for my 15 year old - while her 13 year old sister wandered away to craft with the younger sibs), by measuring across from point to point.  The final snowflake was a little squished, but it was difficult to see where...

...until we (being a puzzle fanatic, I couldn't help jumping in when A abandoned ship) used loose craft sticks to outline the triangles from the first...

...second...

...and third iterations (or phases) of the snowflakes.  Suddenly, we could see the shape in a whole new way...

...and were able to straighten it right out,  and piece together smaller versions of the second iteration star, and third iteration snowflake in the center with no trouble at all.  Which brings me to my favorite feature of fractals...

...they're just so pretty!