Holiday Earthquake Songs

Students had an option to create an earthquake song using a holiday tune.  See some of their creative work below...

Earthquake Unit

Our next unit covers earthquakes.  Unfortunately, winter break is right in the middle of this section.  To review over the break, you might want to make flash cards for the key terms.  I like to use flashcardmachine.com to make online flash cards.  Give it a try if you have never used it before.  You might also enjoy using some of the tools offered at bighugelabs.com.  I used the motivator to make the flashcards below.  Check it out to see some of the other great tools they offer.

Earth's Surface

The Earth has not always looked the same as it does today. Over the last 100 years, scientists have gathered much evidence to show that the Earth has changed.

In the early 1900's Alfred Wegener proposed that the continents were once joined together as a supercontinent named Pangaea. He had several pieces of evidence to help prove his theory...the same fossils can be found on different continents, mountain ranges line up when the continents are moved together, the shape of the continents match like puzzle pieces, and climate evidence suggests that Africa was once cold enough to have glaciers and Antactica was warm enough for tropical plants. Unfortunately, Wegener could not explain HOW the continents moved, so his Theory of Continental Drift was not accepted.

In the 1950's, new technology (sonar) allowed scientists to study the ocean floor. There, they discovered a huge mountain range called the Mid-Ocean Ridge. This is the longest mountain range in the world. Upon further investigation, scientists realized that magma was squeezing through an opening in the ridge and was pushing older rock to the sides. As rock gets pushed to the side, continents also get pushed along. This process is referred to seafloor spreading and it helps explain Wegener's theory.

Today, scientists use the Theory of Plate Tectonics to explain how the continents have moved. This theory states that the lithosphere is broken into several pieces, called tectonic plates. These plates float on the asthenosphere and are in constant motion. Scientists believe that convection currents in the mantle, as well as slab pull, cause the plates to move. There are 3 different types of plate boundaries...convergent (coming together), divergent (moving apart), and transform (sliding past each other).

California is very tectonically active. Down in Southern California, the San Andreas Fault separates the North American Plate from the Pacific Plate. Movement along this transform plate boundary creates earthquakes. In northern California, subduction of the Gorda and Juan de Fuca Plates is responsible for Mt. Shasta and other Cascade Range volcanoes.

The Earth's surface has changed alot over the past 4.6 billion years. Even though the plates are only moving a few centimeters per year, they will continue to change the face of our planet.

Earth's Interior

Over the past couple weeks, we've been focusing on the interior of the Earth. We learned that scientists use seismic waves to determine that there are layers. When the waves pass through a layer that has different properties, the waves bend. We also learned about the 4 main layers of the Earth...the crust, mantle, outer core and inner core. They all have very different properties. Refer to your notes if you can't remember how they're different from each other. In addition, we learned about 2 very special layers: the lithosphere and the asthenosphere. The CRUST AND THE UPPERMOST MANTLE make up the brittle outer layer called the lithosphere. This layer is broken into large pieces called plates. We'll be learning more about these in the weeks to come. The asthenosphere is a thin layer directly below the lithosphere. This layer is slightly melted and acts kind-of like silly-putty...moving very,very slowly.

We also learned that there are convection currents in the asthenosphere and in the outer core. The currents of the outer core create Earth's magnetic field.

Last week we started working on the interior of our Earth models.  Pictures below.

Have anything you want to share about the interior of the Earth? Did you find anything to be particularly interesting?

Observations

It is important to make accurate observations in science.  In class, students had to make observations to differentiate between several types of sands...

7 Habits

We've been spending a lot of time talking about skills that will help us be successful.  The 7 Habits of Highly Effective Teens can play an important role in your life.  In the video below, Patrick and his father show us the power of these habits.  Which habits do you see?  What crosses your mind when you watch this?

Paradigms

Today we learned about paradigms. Just because people view situations differently, doesn't necessarily mean that one person is right and the other person is wrong. A lot of times it's just a difference of opinion. If you can understand another person's point of view, it might help you solve a problem.

Does the picture above show a young lady or an old lady? Both paradigms are correct.  If you can't see the old lady, maybe this will help...

WELCOME!!

Welcome to Ms. DeGraff's science blog. I will be using this site to keep parents and students up-to-date. Check back frequently to see what we're studying, to participate in polls, to see class pictures, class video's and more.

This will be an interactive site where parents and students can leave comments. You do NOT need to set up an account to leave a comment. Follow the directions on the comment page to leave your remarks. But remember, all comments will be reviewed before they are posted. :-)

Again, welcome to 6th grade science! I'm looking forward to a fabulous year!