Tuesday, November 13, 2007

International Polar Year in the Classroom

International Polar Year, IPY, in the Classroom
11.07.07

Both a new school year and the International Polar Year are now underway.

IPY is a coordinated effort by the international science and education communities to learn more about the polar regions and how they impact the rest of the world, including people. The campaign runs for two years, from March 2007 to March 2009, to allow for two field seasons of Arctic and Antarctic research.

In support of IPY, NASA scientists are participating in field expeditions to Earth's polar areas and conducting additional research focused on the poles of Earth and other planets and moons. A variety of NASA and NASA-sponsored projects offer IPY-related classroom activities and resources.

MY NASA DATA NASA
satellites constantly collect data about Earth from space. MY NASA DATA provides small sets of these data in easy-to-access formats for use in K-12 classrooms, as well as lesson plans that incorporate the data. The following lesson plans relate directly to IPY:
-- Comparison of Snow Cover on Different Continents -- Students in grades 4-8 map snow cover on each continent for a given date. They compare the maps with corresponding numerical data, and estimate what percentage of each continent is covered by snow.
-- Snow Cover by Latitude -- Students in grades 6-8 create and compare graphs showing how snow cover changes along a given latitude.
-- Trends of Snow Cover and Temperature in Alaska -- Students in grades 9-12 compare satellite data with ground measurements to examine trends in snow cover and temperature in Alaska. POLAR-PALOOZA

POLAR-PALOOZA is a multimedia effort to explain the importance of the polar areas and clear up misconceptions some people may have about them. Sponsored by the National Science Foundation and NASA, the project brings the poles to life through stories told by scientists who travel to and study them, and through the following hands-on classroom activities:
-- Life in the Cold and Dark: Penguin Adaptation -- Students use plastic bags, vegetable shortening and ice water to simulate the blubber of Antarctic whales, seals and penguins. They also design an original marine animal that is well adapted for the cold, making a picture of it or modeling it with play dough or clay.
-- Graphing Thermal Expansion of Water & Greenhouse Gases -- Students use a flask, cold water, lamp and thermometer to demonstrate thermal expansion of water, a factor that may contribute to future sea-level rise. They also graph yearly concentrations of atmospheric greenhouse gases and analyze trends in the data.
-- Differential Effects of Melting Ice Sheets -- Students use water, ice cubes and a container to show how melting land ice affects sea-level rise differently than melting sea ice.

Satellite Observations in Science Education Satellite Observations in Science Education provides educational resources and data collection tools that help students learn about remote sensing. Hunting Icebergs is a set of three online, interactive tutorials that show students how to identify icebergs in satellite images, and how to measure their size and monitor their movements.

Windows to the Universe
Windows to the Universe is a Web site featuring educational information on Earth and space science topics written at three different reading levels -- elementary, middle and high school. The Earth's Polar Regions section covers topics including polar geography and geology, the polar atmosphere and oceans, polar life, climate change in polar regions, and Arctic cultures. The section also has polar games, classroom activities and virtual postcards from polar scientists in the field.

Other Resources Birth of a Large Iceberg in Pine Island Bay, Antarctica [PDF] -- The front of this lithograph features a sequence of color images showing the breaking off of an iceberg from the Pine Island Glacier in West Antarctica. The first image, from September 2000, shows a crack forming across the glacier. The second two images are from Nov. 4 and 12, 2001, just before and after the iceberg broke away. A detailed explanation and map appears on the back.

Related Resources+ NASA IPY+ Science @ NASA+ U.S. IPYIce: Global Ice and Snow -- This poster features images of an Antarctic ice shelf and an iceberg breaking off from the shelf, snow cover in North America, sea ice and land ice, a surging glacier in Iceland, and a true-color image of the North Pole. Other highlights include an image of a collapsing ice shelf and an account of an expedition to the North Pole. The poster can be purchased from the Central Operation of Resources for Educators, or CORE, as part of a four-poster set on air, land, water and ice.

Tour of the Cryosphere -- This NASA animation takes viewers for a virtual tour of Earth's frozen water, including the icy reaches of Antarctica, the drifting expanse of polar sea ice and the shrinking ice cap around the North Pole. The animation is based on satellite observations. It helps convey the interconnectedness of the cryosphere with Earth's other spheres.

The Science of All Things Squishy

NSF-funded Emory researcher shares the excitement of cutting-edge physics phenomena with kids of all ages

Eric Weeks uses shaving cream and other household items to help students understand complex fluids.

August 16, 2007

Students enter the laboratory to find a collection of mysterious mixtures and substances. They are instructed to examine the materials using their hands or whatever tools necessary. The first sample consists of a white, foamy substance that has been shaped into a tower. They notice the smell seems oddly familiar… 'wait, is that shaving cream?'

Surprisingly, many household items such as ketchup, mayonnaise, toothpaste, hair gel and shaving cream are featured in a seminar class for incoming freshmen at Emory University in Atlanta, Ga. The purpose of the class is to get students excited about science by exposing them to cutting-edge research at the university. The class includes a three-week unit about the properties and behaviors of a group of materials called complex fluids.

Some aspects--students delving into sand boxes and playing with putty-like substances--may seem more appropriate for a kindergarten classroom, but the science behind the activities is actually quite challenging. For example, a mixture of cornstarch and water may feel like clay, but once you stop rolling it around, it flows like a liquid.

So which is it: a solid or a liquid?

According to researcher Eric Weeks, associate physics professor at Emory, it's both. Or better yet, it's "squishy."

That is Weeks' name for materials with both fluid and solid properties. He studies why complex fluids act the way they do, and what causes them to behave differently from simple liquids like water and honey.

His work with squishy substances, along with his commitment to both research and education, earned him a prestigious Faculty Early Career Development (CAREER) award from the National Science Foundation in 2003. CAREER awards are given to the most promising young researchers in science and engineering who also translate their work into significant educational activities.

Encouraging students to question certain aspects of squishy behavior is just one segment of the Emory freshman seminar class. Weeks' colleague, chemistry and biology professor David Lynn, came up with the idea for the class as a method for exposing freshmen to cutting-edge science taking place at the university. The seminar consists of five modules, each three weeks long and focusing on a different area of science. The topics vary each semester and have included physics, chemistry, biology, anthropology, mathematics, computer science, psychology and medicine.

Weeks' module is intended to show students how to think about squishy materials scientifically as well as show them actual research done in the laboratory. As the students explore various types of squishy substances, the laboratory experiments designed by Weeks and other colleagues demonstrate not only that science can be fun, but also that common household materials can be useful aids in understanding complex science concepts.

A how-to article about the classroom unit on squishy materials was published in the May 2006 issue of The Physics Teacher journal. Weeks co-wrote the article with David Lynn and Piotr Habdas, an assistant professor in the physics department at Saint Joseph's University in Philadelphia. The resulting paper was one of the journal's three featured items for the month and was offered as a free download from the journal’s Web site.

According to Weeks, the activities described in the paper can be adapted for different age groups. He and his lab group demonstrated how well the lessons work for younger students when the researchers organized three field trips to the Emory physics laboratory for home-schooled children from kindergarten through eighth grade. The children handled the squishy materials and also got to view them through the lens of a microscope.

"For the youngest kids, we're trying to get across the idea that this is science and it's fun," said Weeks. "They come to the fancy lab setting, and I don't think they expect to see common household items as science."

For more advanced students, Weeks provides a series of hands-on activities that allow the students to investigate why squishy materials differ from solids, liquids and gases, and how microscopic structures could explain the unique, complex properties.

One lab assignment teaches students how to identify the properties of squishy materials. Students are given spatulas and beakers filled with different mixtures. They are asked to observe how difficult each material is to stir.

The students notice that the squishy mixtures have unique and often "weird" properties. The first sample is harder for them to mix as it is stirred faster. Another behaves in the exact opposite way; it is easier to mix when stirred faster. Stick a spatula into the next substance and it stays standing up at a slight angle, as if the substance is a solid. But commence stirring, and the material moves almost as easily as water. Despite the mixtures' unusual behaviors, Weeks noted that the three samples "aren't esoteric: the first is corn starch mixed with water, the second is xantham gum (a common food ingredient), and the third is clay mixed with water."

The varying difficulty of stirring the mixtures demonstrates the property of viscosity, the resistance to flow. By observing how the materials react when force is applied, the mixtures can be classified as specific types of squishy material.

In addition to examining viscosity and other properties of squishy materials, students also learn that the impacts of research on squishy materials are felt in many facets of everyday life, from improving peanut butter processing and packaging to ensuring that low-fat butter still looks and acts like its fatty counterparts.

Weeks explains: "It's the chemists' job to put a chemical in [low-fat food such as butter] so it won't kill you and you won't gain weight, but I'm more worried about its physical properties--does it feel like butter? Move like butter?"

Ketchup is another example of a common squishy food product. It only flows when stress is applied to it, and that's why, according to Weeks and others, a delicate combination of power and skill is required to shake ketchup out of a glass bottle. Now, ketchup companies have switched to plastic bottles and the ketchup can be easily squeezed out.

Outside the realm of food and cosmetic products, Weeks suggests that even humans can be considered squishy. "Water is a huge percentage of our bodies," he said, "so how come we're not liquids?"

When he's not getting students to think about squishy materials in new ways, Weeks is trying to answer some of his own questions in the laboratory. He studies a wide variety of materials, but focuses on a specific type called colloidal substances. These substances are made up of microscopic, solid particles in liquid. Colloidal gels, like yogurt, have a small amount of solid particles but manage to maintain their shape. Then there are emulsions, one liquid mixed into a second, like mayonnaise and oil-and-water.

He uses a confocal microscope to observe the microscopic arrangement, concentration and movement of colloidal particles within substances. For instance, the theory of jamming suggests that the intricate networks of particles within a squishy material allow it to support its own weight. The question of whether jamming could explain the solid-like properties of some squishy materials remains unanswered by physicists.

Weeks' most recent research focuses on how the behaviors of colloidal substances could relate to regular solid materials, like glass. His lab group compared solid-like properties of pastes when confined to small spaces to the transition of glass to a solid state. Their experiments could build on earlier work done with thin polymer films and other glassy materials.

Weeks believes that thinking about this type of complex science is within the understanding of young students. By opening his lab doors to local schoolchildren and providing them with hands-on access to physical phenomena, he is helping young scientists realize that even an ordinary, everyday object can yield great discoveries.
--
Caitlyn H. Kennedy, (703) 292-8070 chkenned@nsf.gov
Investigators Eric Weeks

Related Institutions/OrganizationsEmory UniversityEmory University
LocationsGeorgia

Related ProgramsFaculty Early Career Development (CAREER) Program
Related Awards#0239109 CAREER: Static Properties and Dynamical Behavior of Jammed Systems
Related WebsitesEric R. Weeks homepage at Emory University: http://www.physics.emory.edu/~weeks/Physical Review Focus article about recent experiments: http://focus.aps.org/story/v20/st4