Monday, December 28, 2009

Try Engineering

I found Try Engineering looking for some fun interactive games for my kids on the web. The site is for people interested in engineering careers and so has a lot of information about careers and schools.

Two tabs are of interest in our house. One is the Lesson Plans tab that has a long list of interesting engineering activities for either homeschool or co-op. You can download an 8 page pdf catalogue of all the available plans. The other is the Play Games tab. They have 4 interactive activities produced by the site--Bionic Arm Design Challenge, Questioneering, Design a Parachute, and PowerUp. They also have a good-sized list of other interesting engineering games. I showed this to Ds#2 just before he went to bed and now he can't wait to get on the computer in the morning!

Saturday, December 26, 2009

BioEd Online

The latest great science web resource I found is BioEd Online and its companion site, K8 Science. The sites have news, presentations, slides, lesson plans, and teacher resources for biology. While the sites cover relatively few topics in biology, they still have a decent repository of good quality resource available for free.

The sites have a lot of information about laboratory techniques, including a sheep dissection video, measuring and counting with a light microscope, micropipetting, dilutions, and more. K8 includes some physical science topics as well. Despite their limited subject coverage, they have managed to put out quite a bit regarding embryonic stem cells; unfortunately they have no information regarding other sources of stem cells. They have a presentation on cloning, too.

Overall the sites are a great place to look for ideas or to supplement something you may be doing already.

Thursday, December 10, 2009

Geminid Meteor Showers

The Geminid Meteor Showers have begun and are due to peak at 2 am on December 14th!

From Universe Today:

Occurring every year in mid-December, the Geminid meteor shower is commonly referred to as the most reliable meteor shower of the year. That is, it almost always puts on a great show!

The Geminid meteor shower is sure to be a stunning show this year, as the Moon will not be visible at night, so its glow will not impede your meteor viewing ability. In addition, the Geminids' radiant is favorably positioned for most viewers at this time of year.

Can I shake my kids out of bed at 2 am? Our homeschooling friends up the street live on the top of a treeless hill that would be perfect for viewing...

Sunday, November 22, 2009

Rock and Mineral Show

As part of our geology study we went to a local rock and mineral show. It is a great opportunity to collect minerals and to see where locally people are finding them. This is our first visit to one of theses shows; someone on the AtHomeScience Yahoo group suggested this wonderful idea.

Any child that went to the show got a grab bag of various rocks, and then my kids bought a few, too. The 5 rocks along the bottom of the picture were bought while the rest came in their grab bags.

Ds#1 noticed that one dealer was selling rocks that looked very similar to one he had recently found. We knew it was an igneous rock, granite in particular. It had no pick feldspar though it can be white. The specimen is striking for the many black crystals in it. The black crystals turn out to be biotite, a type of mica; we could tell because it was easy to flake. And since the rock also has muscovite mica, it is called binary granite.

BTW, the University of Pittsburgh and Cal Poly Pomona have informative and pictorial sites for identifying igneous, metamorphic, and sedimentary rocks.

Saturday, November 21, 2009

Saturday Science Challenge #13

Layers of the Earth

The earth has 3 basic layers--the crust, the mantle, and the core. Texts will emphasize the thinness of the crust. Making models is a wonderful way to demonstrate this, though I found my kids were particularly impressed by this demonstration.

The earth is not perfectly spherical, and the crust of the earth is irregular, so exact numbers are not really possible, but these are the ones we can use for this activity:

Radius = 6378 km
Distance to core edge = 2890 km
Distance to mantle edge = 35 km (from Wikipedia)

Take a measuring tape at least 6 m long; have someone hold it in place at the "center" of the "earth." First measure out to 2.73 m. Holding chalk and the edge of the tape together, draw a circle, or at least an arc; this first line is the edge of the core. Now bring the tape out to 6m and draw a second arc; this second line is the edge of the mantle. Ask your kids, "How thick is the crust in this model? How much longer do I extend the measuring tape to draw the crust?" Have them mark where they think the line would fall.

Answer: 3 cm

For advanced students, have them calculate the ratios. I choose to have the edge of the mantle to be 6 m, so how large is the full radius for the model? The actual distance from the center of the earth to the mantle's outer edge edge is 6378 km - 35 km = 6343 km. Now set up a ratio:

distance to outer mantle (6346) is to earth's radius (6378) as model distance to outer mantle (6 m) is to model radius (rm).

6346/6378 = 6/rm --> (6378)(6) = (6346)(rm) --> (6378)(6)/6346 = rm
rm = 6.03

You can set up a similar ratio to check the edge of the core.

Sunday, November 8, 2009

Saturday Science Challenge #12

Basic Rock Identification

Around here we rarely find rocks made of a single mineral that we can identify through color, luster, streak, hardness, and cleavage, but you can classify rocks into their three basic classes: igneous, metamorphic, and sedimentary.

All you need is one hammer and goggles for everyone participating. A geologist's pick hammer is most effective though this can be done with other hammers. And you need to find a flat, hard surface on which to do the cracking.

You can play the Rock Type Game at Geology For Kids as a warm up. You can also read the classic A First Look At Rocks by Millicent Selsam, or DK e.Guides Rocks and Minerals to get an idea what to look for when classifying them.

Cracking them open, as well as wetting them, really helps to see crystals and layering. And I didn't have to ask twice if anyone wanted to do this activity. For older kids, have them try to identify the specific types in each category. They can also map the location of their rocks, and see if different locations have different predominant types. The Moh's hardness scale is helpful for this, especially the hardness of common items you can use to test your samples. For advanced students, check out the igneous rocks, metamorphic rocks, and sedimentary rocks classification pages.

These two rocks are the same specimen. The picture doesn't show how much more lustrous the inner rock is compared to the worn outer surface.

It's granite, an igneous rock.

Monday, October 26, 2009

Bedrock Samples

Whether it's Nature Study or Geology, it's great having an environmental engineer for an aunt (my sister-in-law.) Not only does she know all the plants in the area, she gives you gifts like pike hammers and bedrock samples. These arrived today. She included an informational sheet as well as a pamphlet about Rhode Island bedrock, complete with a geological map!

These bedrock core samples are the metamorphic rock gneiss formed from granite, distinguishable by its distinct banding. It contains quartz (clear to gray), biotite (black banding), and feldspar (pink.) Some samples may contain flecks of pyrite (Fool's gold.)

The samples are best viewed wet. Why? Think of clear plastic wrap--when you crinkle it, it becomes white because the light is reflected by the countless surfaces it now has. The uneven rock surface (even though these are pretty smooth from the drill) is "smoothed out" by water and so the colors are more intense. This is similar to polishing rocks.

All of these pieces come from the same core sample beginning at about 40 feet deep. Each piece is marked with the depth at which that piece started. The breaks come from pockets of ground water. You can clearly see how the stone changes with depth. Yoou can't tell in these pictures but the deeper stone clearly contains a lot more feldspar than the more superficial stone, which has more biotite banding.

Saturday, October 24, 2009

AtHomeScience Yahoo Group

Click to join AtHomeScience

Finally, I have activated the Yahoo Group that I created back when I created this blog. I've added a button to the sidebar if you would like to join. Here is the description:

Everyone is welcome! This group has many Catholic members, including the moderator; as a result, please keep the following in mind:

Please no discussions about "young earth" or "Creationism" and please note if a resource has that perspective. I greatly appreciate families of faith with this perspective; however, information about these resources are available elsewhere, and discussions on this topic tend to get extensive and are without resolution.

Many wonderful secular resources will be discussed, and most of them have no reference to Christianity. Those that do will be discussed in light of their view on Christianity. On some occasions, discussions about Science and Catholicism will take place as well. Any anti-Catholic comments will no be posted.

May this list be a blessing to your own science homeschooling journey!

Saturday, October 10, 2009

Geology Study Resources

We are taking up earth science at our house this year, and we are exploring it with our small co-op (3 families, 11 children under age 11, 8 of which are school-aged) We have had a lot of fun so far investigating geology, so I thought I would share some of my resources.

I am using Be Your Own Rock & Mineral Expert by Michele Pinet as our spine. This thin hardcover works well to outline lessons, including activities. It is particularly good at describing techniques and making tools for rock hunting, and then for testing samples. You will need other sources for specific identification. Unfortunately this book is out-of-print and quite expensive; my copy is from our library. This is actually geared to high school kids but it is easy enough to adapt.

I have found several wonderful living science books, most of them written 20 or more years ago. Many of these, however, are still in print and some have even been updated! In fact, the only two on this page that are out of print are the books by Pinet and Selsam.

Some of these are strictly about rocks and minerals while some relate to the rock cycle or the earth's composition. I find it helps kids understand and distinguish igneous, sedimentary, and metamorphic rocks. One of our family's favorite authors is Milliscent Selsam, and A First Look At Rocks is no exception. The black and white pictures have obvious limitations, but the writing is just spectacular juvenile science. The book is a great introduction to the three types of rocks and the characteristics of each, so you can go out and start classifying your finds. Her books, unfortunately, are out of print but they are readily available on the used book market. Another favorite of ours are books from the Let's Read and Find Out series; two of them relate to our geology study.

As for actual pictorial identification, rock and mineral books are plentiful on library shelves. We happen to like the Basher Science books because they are so whimsical, the information is in bite-sized pieces, and my kids love to look at them, and the newest addition is Rocks and Minerals: A Gem of a Read.

We have subscriptions to Discovery Streaming, which has many related videos, though I liked the ones from United Streaming that I could link to for free from this neat site about the rock cycle called Rocks to Soil.

We also use Explore Learning, which has some great Gizmos. The Rock Classification Gizmo and the Rock Cycle Gizmo and the Mineral Identification Gizmo all fit right into our study. You can try them for 5 minutes at a time for free each time you visit the site, and Homeschool Buyer's Co-op is currently offering a group buy.

Our little class is about to move on to collecting and testing sample. I even bough a small amount of HCl from Home Science Tools for when we get to mineral identification. I hope the weather doesn't get too cold yet!


How could I forget these three wonderful books (thanks Jennifer!):

Thursday, September 10, 2009

Solubility, Capillary Action, Math, and Art

This week we had a combined art and science project, with a little math thrown in for good measure!

You need a white T-shirt, permanent markers, isopropyl alcohol (we used 70% though 90% would be fine too,) a dropper bottle (we used a non-medical syringe,) a large plastic cup, and a rubber band. Here you see the boys posing with their new T-shirts ready to start the project.

Slip the plastic cup inside the T-shirt so the opening of the cup faces towards the front panel of the shirt. On the outside of the shirt, pull the shirt tightly over the cup and put the rubber band around the top to secure it.

Put spots of various colors on the section of the shirt secured to the cup. You can put wavy lines, too, if you like the effect.

Here's the science part. Permanent markers are not soluble in water, but they are in alcohol. Fill your dropper bottle with the isopropyl alcohol and drop in onto the decorated section. Because the permanent marker is alcohol-soluble, the ink "runs." Capillary action moves the ink along the fabric.

Because the syringes are graduated, the boys made up math problems as they went along, like, "Mom, if I had 30 mm of alcohol to start and now I have 10 mm, how much did I use?"

Here are the boys with their finished projects.

We did have a PROBLEM though. I rinsed the shirts in water before washing them, but all the ink washed away. Next time I am going to rinse them well again, then run them through the dryer to evaporate off all the alcohol (it is very volatile, which is why it has such a strong odor) before washing it. The boys have been bugging me to get more shirts ever since.

Wednesday, August 26, 2009

One Lovely Blog Award

Thank you Sara in the Woods for this award posted on her blog The Forest Room. Just the graphic alone makes this a neat meme to pass along! I am a tea drinker; I have an entire cabinet filled with different varieties and accessories, with more loose teas in my ginger jars.

Here are the rules of this award:
Accept the award, post it on your blog together with the name of the person who has granted the award, and his or her blog link.

Pass the award to up to 15 other blogs that you’ve newly discovered. Remember to contact the bloggers to let them know they have been chosen for this award.

  1. This needs to go back to Sara and The Forest Room as her blog is a wonderful discovery!
  2. Learners At Home are from my neck of the woods...
  3. is Every Day Best (and a long lost college friend!)
  4. Live Life with Your Kids is another neat CMer blog.
  5. Over the summer I found Catholic Cuisine and we are actually going to incorporate it into our TORCH classes this fall. They have the lovely tea set up in the corner, too.
  6. Heart of a Mother is another lovely and inspiring blog new to me.
I could also give this to most of my long time favorites, too!

Sunday, August 23, 2009

Free Museum Day is Approaching

Saturday, September 26th is Museum Day, when loads of participating museums offer free admission. Which one shall we go to the year?

Sunday, August 9, 2009

Living Science Author: Robert Gilmore

I only picked up The Wizard of Quarks yesterday at my favorite used books store, and so I have only read a little of it. Yet in researching this book and others by Robert Gilmore, Once Upon a Universe, Scrooge's Cryptic Carol, and Alice in Quantumland, I knew I had to post about these marvelous living science books.

Each book explains complicated physics through a modern retelling of a classic fairy tale. The Wizard of Quarks is an introduction to atomic physics told through Frank L. Baum's classic. Grimm's Fairy Tales are used to explain the universe in Once Upon a Universe: Not So Grimm Tales of Cosmology. Three ghosts visit a descendant of Dicken's famous character in Scrooge's Cryptic Carol: Visions of Energy, Time, and Quantum Nature. And then there's Alice in Quantumland, with the obvious nod to the Lewis Carroll classic.

Make no mistake, these are college-level books dealing with college-level concepts. I noticed that several comments on Amazon mention these books being enjoyed by elementary students, they are that fun, even if they didn't get all the concepts. It seems only scientists pan the books, and not for the content but rather for the fairy tales.

These books are rather pricey as new hardcovers but used copies are readily available at good prices. (I've already ordered the other three myself.) I will post a full review on Shelfari as soon as I finish these delightful finds!

So far Dorothy has encounter the very large witch of mass, who explains how her strength is far, far less than her sister, electromagnetism. She has two other sisters, too--strong (color) interaction and weak interaction.

Dorothy has also met the Observant Scarecrow in an electron probability field...