Friday, July 31, 2009

30 Second Science - Subjective Colors and Benham's Top

Here's an extension of, or maybe a take off from, the optic top we made earlier in the week. This time, instead of seeing colors blend together as the top spins, the eye sees flecks of color (known as subjective color), on a spinning black, and white disk.

We found several printable versions, as well as wonderful explanation of what scientists know, and don't know, about the colors seen on the disk, here, at Neuroscience for Kids.

It caught the children's interest, when they realized they were each seeing different colors on the same spinning top. That effect has something to do with the way the rods, and cones of the eye percieve different wavelengths of light, but scientists are still uncertain as to what is going on. It's is particulary interesting, when you consider C.E. Benham noted the phenomonom, more than 100 years ago, and the answer to what is causing it, remains a mystery of science.

What a great challenge for the kids!

It's great to be a homeschooler.

Thursday, July 30, 2009

Recycling Cereal Boxes into Round Craft Boxes

Making round craft boxes out of recycled cereal boxes ,is not only a fun, frugal, and environmentally friendly craft project, it's also a great "real world" math exercise. In order to figure out the diameter of the box, against the length of cardboard you have available to turn into the sides of the box, you need to know how to figure out the circumference of a circle, and also to use algebraic skills to back track from the length of the side, to the diameter of the circle. Of course, if that gives you too much of a headache, you can always eyeball it, and use trial and error.

To make a craft box, open an empty cereal box at it's side seam, and lay it out flat.

Once you've determined the size of the cereal box, and figured the size of the circle needed for the top, and bottom of the craft box, you can find something to use as a guide for drawing your circles. I had about 11 inches of workable cardboard on my cereal box. I used my coffee cup as a guide to draw the circles. The coffee cup has a diameter of 3.25 inches. That makes its circumference, 3.25in x 3.14in, or just over 10 inches.

Draw two circles, and cut one just inside your drawn line, to use for the base of the box. Cut the other, for the lid of the box, just outside your drawn line.

For the sides of the box, especially if your box has any glue lines on the inside, the best portion to use, is what use to be the short side of the cereal box. Cut about a quarter inch out from the fold lines, that once made the corners of the cereal box.

Then measure in to the side, about a half an inch from the fold lines, and cut along that line. The wider piece will be your box base, and the narrower piece will be the lid.

Trim the box base piece, a little shorter than the box lid piece, and then make slice cuts from the outside of the fold lines, to the fold lines, every quarter inch or so. We hadn't made our slice cuts yet, in the picture below, but you can see them in the pictures that follow.

Bring the short ends of the base piece together, to form a circle with a slight overlap, and paperclip in place. Do the same with lid piece. Fold the sliced pieces toward the center of the circles, using the fold line of the box.

After you try the lid on top of the box, to make sure it will fit, glue the overlaps, and replace the paperclips, until the glue is dry.

Once the glue is dry, remove the paperclips from the base piece, and glue the smaller circle inside of it, so that the printed side of the cereal box is up.

Place some heavy books on top of it, until the glue is dry.

Repeat for the lid, except you should place the circle, printed side down, on top of the lid piece. Again, use heavy books, to hold the circle in place, until the glue is dry.

Once the glue is dry, your box is ready to use, or decorate, as you would any paper mache box from the craft store.

We wanted a box to hold the bits of dinosaur bone, that we were given on the Dinosaur Trial, so we printed out a picture from our trip to glue to the top (this involved knowing the surface area of our circle). We finished the box off by covering it in bits of green, and yellow tissue paper.

On our second box, we added some stitching, and foam letters, an idea that we saw at Homeschooling in the Rose Garden. We love the look, but the stitching proved too hard for little hands. We might try a preschool version, next time, by pre-punching holes, and letting them stitch yarn through.

That will have to wait until we have another empty cereal box, because our third craft box, was reserved for a project the girls have been wanting to try with a homemade sculpty type clay. We still have a little fiddling to do with our clay recipe (as you can see from the cracks on the lid of our toad stool box), but that's a post - and a math/chemistry lesson - for another day.

It's great to be a homeschooler.

Simple Doorway Puppet Theater

I guess I have the Nick Jr. website to thank for this idea too. They have a pattern for a fancy little felt puppet theater, to be hung on a tension rod across a doorway. The pattern was a little fussy for me, but the use of the tension rod, caught my attention.

We picked up two of them at the local big box store, for $3.89 a piece. I added a valance, and single panel of a curtain set, that used to hang in the girls room when they were younger (I think you could just as easily drape a sheet over one rod, in a pinch, though).

Throw in a few puppets... attentive audience...

...and you have a really simple, and inexpensive, doorway puppet theater.

It's great to be a homeschooler.

Wednesday, July 29, 2009

Organizing School Supplies

It's that time of year again, when glue sticks, pencils, and crayons are at their lowest sale price. The problem is, where to keep an entire years worth of supplies. Nick Jr. has one of the best suggestions I've seen yet. They used an inexpensive, clear, over the door shoe organizer (you know the kind, that is totally useless for keeping shoes in) for all those supplies, you need handy, but out of the way.

We use a linen closet to keep all of our school books, and games in, so an over the door, hanger is perfect for us. I'll have to do a bit of rearranging, and probably condensing, but I'm really pleased with how it's working out. I picked up two, so that I could hang one in the entryway coat closet, for mittens and hats this winter. But, I'm thinking I might need a third, for science supplies too. If only I had another closet, I could trust the kids to stay out of!

It's great to be a homeschooler.

Tuesday, July 28, 2009

Primitive Yarn Dolls

My older girls made yarn dolls at a pioneer day celebration a couple of years ago. They don't look like much, but they've survived, and continued to be played with, after two years. They've lasted long, in fact, to attract the attention of my younger daughters, who wanted to know where their yarn dolls were.

I understand, that grandmothers have been demonstrating the art of yarn dolls to their grandchildren for generations. I guess I was contented enough watching Saturday morning cartoons, that my grandmother didn't bother making them with me. At least I don't have any memory of them. Luckily for me, they turned out to be as simple to make, as they look.

We picked a card game box, that was about as tall as we wanted our dolls (our box was 6 and 1/2 inches tall - a book, or a piece of cardboard would work equally well), to wrap our yarn around. Before we started wrapping the yarn, we laid one piece of yarn, horizontally across the top of the box.

Then, we wrapped our yarn, loosely, about 40 times around the box.

We slipped the yarn off the box, and tied the horizontal piece, tightly around top of loops, and cut open the bottom of our loops.

We smoothed the yarn together, and tied another piece of string around the whole thing, about an inch down from the top, to form the head of the doll.

We separated out about 15 pieces of yarn, on each side for the arms, and then tied pieces of yarn around each wrist, trimming off the ends, to make the hands.

We tied another piece of string, about an inch below the arms, to form the waist. To make a girl, we left the bottom as it was, suggesting a skirt. To make a boy, we separated out legs, and tied them at the ankles.

Finally, we switched to a different color of yarn for the hair. We wrapped it around the width of our box for girls hair, and around our fingers, for boys hair. Instead of placing a piece of yarn horizontally under the loops, like we did for the body, we used a yarn needle, to pass it under the knot on the top of the head.

Then, after we removed our hair loops from the box, we cut the bottom of the loops open, and laid them across the head, using our sewed in piece of yarn to tie the hair on with.

Our girl's hair has a little wave to it, because the yarn had been previously crocheted, and then unwound.

For the boy, we trimmed the hair quite short.

These dolls can be fancied up with faces, and clothes. My girls were content with the simple version, but I found a few sites such as Making Friends, AOK Corral, and Craftstylish, that have some pretty nifty adaptations, if you're interested.

It's great to be a homeschooler.

Monday, July 27, 2009

Mini Chocolate Chip Cookie Bowls

I've wanted to try this Family Fun idea, since The Idea Room featured it back in May. Last night, I finally got around to it. We used the original Family Fun recipe:

  • 1/4 cup shortening

  • 1/4 cup butter, softened

  • 2/3 cup sugar

  • 1 egg

  • 1/2 teaspoon vanilla extract

  • 1/2 teaspoon salt

  • 1/4 teaspoon baking powder

  • 1 1/2 cups flour

  • 1/4 cup mini chocolate chips

As is normal for these kind of recipes, you cream together the first five ingredients, sift together the next three, and mix them in to the first bowl. Then, you add the chocolate chips.

At this point in the recipe, we diverged from the Family Fun directions. Theirs called for dividing, flattening, and chilling the dough for two hours, and then rolling it out, and cutting it into rounds. That was way too fussy for us! So we just rolled our dough into two inch balls, and then patted them flat by hand.

Before we did that though, we prepared a mini muffin pan. Family Fun used a regular size pan, but we only have a six cup pan, in that size. Besides that, we thought little bowls might be fun. We flipped the pan over, and covered the bottom of every other cup, with tinfoil (I used scissors to cut the squares of tinfoil to about the right size). Then, we sprayed the pan, and tinfoil, with non-stick spray, and smushed our balls of dough down over the tinfoil covered cups. Finally, we baked them for about 12 minutes at 375 degrees Fahrenheit.

After, they had baked, and cooled, we removed them from the pan, peeled away the tinfoil, and filled them with ice cream. We were pretty pleased with the results. The only change we might make next time, is to make them a bit thinner (I suppose that's what all that refrigerating, and rolling in the Family Fun directions, was all about).

Tip: Roll any unused dough into one inch balls, and freeze in an air tight container (or even a freezer bag set on top of a cookie sheet). We keep a container of frozen cookie dough in the freezer, and add to it whenever we've got extra dough. Then, when we want some quick cookies, we pop a few of the frozen balls into the oven at 350 degrees Fahrenheit for 10 to 12 minutes, and we're good to go.

It's great to be a homeschooler.

Sunday, July 26, 2009

30 Second Science - Stroop's Effect

Here's a test that's actually fun to take.

Time yourself as you say the colors, that the words below are written in. Don't worry about what the words are, just say the colors they are written in.

Blue Orange Red

Green Yellow Purple

Pink Brown Black

Now time yourself again as you do the same thing with the words bellow. Say the color of the word, not the word itself.

Blue Orange Red

Green Yellow Purple

Pink Brown Black

If your like most people, it took you about twice as long to say the colors of the words in the second group. This effect is named after Ridley Stroop who first published the effect in English in 1935 (per Wikipedia).

Another fun extension of this test, would be to write out the words in a second language that you are familiar with, and time yourself again. I'd like to try this with a language that uses symbols, such as Chinese, but we need to spend a little time reviewing our language skills first.

It's great to be a homeschooler.

Saturday, July 25, 2009

30 Second Science - Optic Top

The idea for this experiment came from the A.C. Gilbert's Discovery Village website, here.

Cut out a number of circles from card stock, or paper glued to thin cardboard, like a cereal box.
We used a round lid for a guide.

Draw lines through the center of the circle to divide it into fourths, or eighths.

Color in the "pie" pieces in different colors. We used primary colors.

Stick a sharpened pencil through the center of the circle.

Spin the circle, and pencil, like a top. You might need to balance it between your fingers as it spins, to keep it from falling over, and you'll want to place a paper underneath, or you'll be drawing on your table.

Watch the colors as the top spins. The colors merge together.

It's a similar effect to what we saw with the thaumatropes we made a few months ago, except that it only suggests color to the brain. What I mean by this, is that each of the children in our house, saw the color differently. Using our disk that was half red, a quarter blue, and a quarter yellow, one child saw orange, one saw green, and one saw the colors underneath, with a glowing green over the top.

Scientists are still a little unsure as to what goes on between the brain and the eyes, that cause this optical illusion. It's the tip an interesting iceberg of study into neuroscience - but that's matter for another post.

It's great to be a homeschooler.