Monday, December 31, 2007

Draw a Scientist Test

How do you find out what kids think of scientists? Have them draw a picture!

This week I was working on a story about CSI and how it's changed public perception. For DAs, the so-called "CSI Effect" has been a problem: juries expect to see the full array of high-tech analyses before they'll convict a defendant (whether it's needed to prove their guilt or not).

But for kids, the "CSI Effect" is different. Researchers have found that the typical scientist as drawn by middle school students is no longer a nerdy white guy in a lab coast with thick glasses and wild hair. In other words, they don't look like the fellow below, from today's Albany Times Union:

A Rensselaer Polytechnic Institute scientist has discovered a fact about mosquitoes that may turn the treatment model for malaria upside down.

"The mosquito is as much a victim as we are, but nobody thinks of the mosquito that way," said Robert Lindhardt, a biochemist and acting director of RPI's Center for Biotechnology and Interdisciplinary Studies.

Instead, they draw scientists who are more "realistic," researchers say. Something like the woman below, who plays a forensic scientist on CSI: Miami, as quoted in yesterday's Parade Magazine:

Q Your item on Emily Procter made me wonder: Why do she and the other women on the CSI shows, such as Marg Helgenberger and Melina Kanakaredes, choose to show so much cleavage?
E.G.J., Lothian, Md.

A “You don’t really think we dress ourselves, do you?” asks Procter. Costume decisions lie with the producers and wardrobe staff, who seem to follow the philosophy “the deeper the cleavage, the higher the ratings.”

Friday, December 28, 2007

An Education Rant

It was probably ten years ago or more than I attended a workshop given by Charles Scaife
, then a professor of chemistry at Union College in Schenectady, NY and his wife Priscilla on doing hands-on science with kids. Talking with Scaife afterwards for a story that ran in one of the local newspapers, I heard how most elementary school teachers have little background in science, and how rarely they feel comfortable teaching it. And that was before George Bush's federal No Child Left Behind school policy put the pressure on teachers to prepare children for high stakes standardized tests in reading and math that leave little room for exploration and wonder. Even after school, homework overload also steals times from kids who might otherwise be messing around with stuff that could lead to scientific insights (but that's another rant). The result Scaife said, was fewer students interested in science in the upper grades, and college freshman who can spit back the right answer without any understanding of the underlying concepts or how to apply them.

I bought Scaife's spiral-bound book of experiments like the ones the couple set out for parents and kids at their workshop to use at home. Although we tried just a few (not always successfully, as seems to be par for the course with use), that evening was definitely the catalyst for this Home Chemistry project we're engaged in this year.

Charles Scaife, whose presentations were the subject of a front-page story in The Wall Street Journal, and subsequent stories in USA Today, the Christian Science Monitor, and Education Week,died in 2003. Priscilla carries on the tradition of introducing the magic of science to children.You can check out the Scaifes' experiments for yourself at the Union College website.

Monday, December 24, 2007

Still growing

The alum crystals are slowly getting bigger. But a lot of the alum in solution in the cups crystalizes out into separate tiny little crystals. Whenever there are too many little crystals in the cup, we decant the solution into a clean cup. And I put the little crystals into a third cup I started.

At first nothing grew. I figured there wasn't enough alum in the solution. But little by little I added more crystals and let the water in the cup evaporate.

Then the other day, I glanced in the cup and saw these, lying on the bottom:

Without the food coloring, they look like diamonds waiting to be put in rings. So cool! All the crystals are flat on the bottom, though. I tied one on a string to see if it would grow, and if it would even out on the flat side. Updates in a few days.

Tuesday, December 18, 2007

Christmas Candy Chemistry

We made molasses popcorn balls for our homeschool bookclub meeting. Making candy involves heating the sugary mixture to different temperatures according to the texture you're looking for -- sticky, stretchy, chewy, hard, etc. We used a candy thermometer I happened to have as well as the "drop some in a cup of cold water" method, until we got the texture we wanted.

The molasses actually came out pretty good (one of the moms couldn't stop eating it; I finished off the leftovers this afternoon). But I had made the popcorn in a big spaghetti pot and didn't take out all the unpopped kernels in the bottom, so they got stuck into the balls as well. I made a note in the recipe for next time.

Here's the recipe (reduced by one-fourth, because of the size of the molasses bottle we used):

Molasses Popcorn Balls

1 1/2 cups popcorn kernels
3/4 cup sugar
1 1/2 tablespoons butter
1 1/2 cups molasses
pinch salt
3/4 teaspoon baking soda
3 cookie trays, lined with waxed paper

Pop corn and turn into bowl. Remove unpopped kernels!

In a medium sized to large pot, boil Molasses, sugar, butter, and salt, stirring occasionally until mixture forms hard ball in cold water.

Remove from heat, add baking soda and mix well. It will froth over.

Pour over popped corn, stirring so that each kernel is coated.

Form into a ball with well buttered hands QUICKLY! Place on waxed paper to cool.

The graphic above illustrating the science behind candy hardening is from The Exploratorium's interesting Science of Cooking webpages.

Thursday, December 13, 2007

Big Alum Crystal Update

After a gravelly start, our alum crystals are growing nicely.

Just leaving the solutions sitting in clean cups for a couple days before we could get back to them allowed some good-sized seed crystals to grow. Each kid picked one and tied it to a string. By day two you could see the crystal bulging around the string, and by today, day three, the crystal had swallowed the string and kept growing around it.

Because the boys put food coloring in their water, the strings can be seen clearly. (The string picked up more of the coloring than the crystal, which shows just the slightest tinge of color.)

Oh, I did end up saving the tiny crystal grains, re-melting them in hot water, and putting a leftover seed crystal into a third cup to see if I could get it growing. But I think I put too much water in for the amount of alum, because the seed just disappeared in the solution. I keep adding more alum as the kids clean out the little grains from the cups (by decanting the solution into a clean cup). Eventually, I figure, it should evaporate enough to become saturated and start to form crystals.

Tuesday, December 11, 2007

Chemicals for Your Kids' Cold

From the Washington Post:

With many children's cough syrups being pulled from the market because they don't work, an old folk remedy -- honey -- may work just as well or better, researchers report.

In a study of kids having trouble sleeping because of cough, a research team at Penn State College of Medicine compared the effectiveness of a little bit of buckwheat honey before bedtime versus either no treatment or dextromethorphan (DM), the cough suppressant found in many over-the-counter cold medicines.

"Honey provided the greatest relief of symptoms compared with the other treatments," concluded lead researcher Dr. Ian Paul, Penn State's director of pediatric clinical research.

An FDA advisory board recently recommended that over-the-counter cough and cold medicines not be given to children under 6 years of age because of a lack of effectiveness and potential for side effects.

"With honey, parents now have a safe and effective alternative to use for children over age 1 who have cough and cold symptoms," Paul said.

Paul cautioned that honey should never be given to children younger than 1, because of the rare risk of infantile botulism. In addition, he noted, cough medicines that mention "honey" on the label actually contain artificial honey flavor.

Honey is primarily composed of fructose, glucose and water. It also contains other sugars as well trace enzymes, minerals, vitamins and amino acids.

And what is dextromethorphan (C18H25NO )?

Dextromethorphan (DXM or DM) is an antitussive (cough-suppressant) drug found in many over-the-counter cold and cough medicines. Dextromethorphan has also found other uses in medicine, ranging from pain relief to psychological applications. Pure dextromethorphan occurs as a powder made up of white crystals, but it is generally administered via syrups, tablets, or lozenges manufactured under several different brand names and generic labels.

When taken at doses higher than are medically recommended, dextromethorphan acts as a dissociative hallucinogen. It produces effects similar to those of the controlled substances ketamine and phencyclidine (PCP), which affords it a high potential for abuse.

(From Wikipedia)

Sunday, December 9, 2007

Crystal Update

The salt crystal gardens continued growing, without any additional ingredients for several days. Eventually, they began to wilt a little.
Here again is the progression:

Which stage do you think is the best?

As for the big alum crystal...

our seed crystals came out SO small that we couldn't work with them.
So we're going to try melting them down (just that little spice container was three bucks)
and start over. I found, and then lost, a link to tips for growing better crystals.
When I find it again I'll add it here.

Tuesday, December 4, 2007

Periodic Tables and Lego Molecules

Becky over at Farm School at Home, a homeschooling blog out of the Canadian wilderness, had a post last week featuring an avalanche of periodic table links. Following a Lego Periodic Table link led me to a University of Wisconsin - Madison site featuring molecules built out of Legos -- with instructions. (The DNA Lego molecule above is from the Lego website -- I had trouble getting an image from the UW-M PDF instructions.)

I'll have to get the kids on this project!

Farm School: Cybils Review: The Periodic Table: Elements with Style!

(Scroll past the book review for the links)

What is alum used for?

We're trying another crystal project from, growing giant crystals of alum. Alum -- or hydrated aluminum potassium sulfate, KAl(SO4)2.12H2O -- is sold in outrageously expensive little containers with the spices. It's used to make pickles crispy.

The kids wanted to know more, so we looked it up on Wikipedia.

You'll find alum in styptic pencils to staunch the bleeding from shaving, and underarm deodorant, because of both its antibacterial and anti-wetness properties.

Oh, and it's an astringent, which is why they can use it in Looney Toons cartoons to shrink heads. And you thought the only thing kids learned from watching Bugs Bunny was classical music!

It's Alive!

By this morning Anthony's crystal garden was trying to climb out of the bowl.
As the day progressed, the turquoise food coloring stopped spreading,
and the bulbous projections sprouted white tips.

John's garden sprouted nicely overnight as well.
Tonight it looks like a bunch of miniature multicolored Afro wigs.

Monday, December 3, 2007

How does your crystal garden grow?

Very well, thank you!

We changed the ingredients...
Mixed them together BEFORE pouring them over our sponge bases...
And in just a few minutes...

Anthony used double the amount of bluing, so his salt solution is more dilute.
(You can see a crystal formation climbing up the side of the bowl.)

John put some dots of food coloring on his.
(Note that the red spots grew the least.)
(I am very happy.)