Project Earth – Making the World a Smaller Place

Project Earth is a global networking website for K–12 educators and the public designed to connect people around the world to help solve environmental problems. Its mission is to generate ongoing conversation and collaboration across national boundaries that collectively lead to positive environmental change. Registration is required and member teachers/schools/classrooms are able to showcase their innovative environmental projects, connect and interact with ecologically-minded people around the world (from Minnesota, to Los Lagos, Chile, to Ulaanbaatar, Mongolia!).  Teachers and students also have the opportunity to participate in environmental contests and earn recognition for efforts.

Last year, Project Earth’s World Environment Day Contest drew winners involved with environmentally conscious projects such as studying how plastic bags affect our environment, and growing food for a school kitchen and composting the waste. Submissions to the 2011 contest are due May 15th. A great project idea for your classroom!

A few  other resources to tap into on this topic include the MSP2 resource guides on Technology and the Environment, Populations and Ecosystems, and Oceans, Climates and Weather.

World Water Day – March 22

International World Water Day is held annually on March 22nd as a means of focusing attention on the importance of freshwater and advocating for the sustainable management of freshwater resources. There are lots of ways to make a difference for people who don’t have access to life’s most basic needs – safe drinking water and latrines. To get started, visit Water 1st’s Youth Involvement website and request a DVD to see and hear about water issues in the developing world. Next, you can “adopt a community” in need of clean water infrastructure. Finally, look on the website to learn about what other schools are doing to tackle this issue and come up with your school’s own strategy for making a difference.

We Want Your Feedback
We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? We invite you to share with us and other readers by posting your comments. Please check back often for our newest posts or download the RSS feed for this blog. Let us know what you think and tell us how we can serve you better. We appreciate your feedback on all of our Middle School Portal 2 publications. You can also email us at msp@msteacher.org. Post updated 4/18/2012.

Snowflakes Grown in Labs Answer Questions About the Ones Falling from the Sky

If middle schoolers are cutting out paper snowflakes for holiday decorations and one student insists on cutting white triangles, that’s okay. The six-sided snowflake is most often depicted, but three-sided snowflakes are not uncommon. They’ve been observed in nature for hundreds of years. Noted snowflake photographer W.A. Bentley (celebrated in the Caldecott Medal Book Bentley’s Snowflakes) and other scientists recorded them.

Physicists Kenneth G. Libbrecht and H. M. Arnold have created triangular snowflakes, as well as hexagons, in their laboratory at the California Institute of Technology. They found that the majority of flakes grown in a vapor diffusion chamber were hexagons but more than they had estimated became triangles, leading them to look for the trigger that turns hexagons into triangular shapes.

According to the authors in their published report, ”We have been studying the detailed physics of snow crystals as a case study in crystal growth, with the hope that developing a comprehensive mechanistic model for this specific system will shed light on the more general problem of structure formation during solidification.”

A single small growth perturbation on the forming hexagon flake resulted in a distorted, or triangular, shape under certain aerodynamic conditions. The perturbation caused the falling flake to tilt up. The airflow around the crystal produced instability in the growth of the facets, creating the triangular shape. After the triangular shape is initially formed, the flake stays triangular during the rest of its fall.

Libbrecht and Arnold point out, “The growth of triangular snow crystals is another piece in the puzzle that describes the many interconnected mechanisms by which complex structures emerge spontaneously during solidification.”

For all those interested in snowflakes, Libbrecht created the web site SnowCrystals.com, with photo galleries of real and synthetic flakes, frequently asked questions, tips on photographing crystals and preserving them, snow activities for all age groups, and more. Libbrecht used a specially designed snowflake photomicroscope to photograph flakes. In 2006, the U.S. Postal Service used his photos as a set of commemorative stamps.

More Snowflake Studies. At Purdue University, a Ph.D. candidate in chemistry, Travis Knepp, has been growing ice crystals in his lab, subjecting the crystals to temperatures ranging from 110 degrees Fahrenheit down to minus 50 degrees. A press release from the university reports that Knepp’s experiments are part of his study of ground-level ozone depletion in the Arctic.

Knepp explains, “Most people have probably heard of ozone depletion in the North and South Poles. This occurs in the stratosphere, about 15 miles up, What people don’t know is that we also see ozone levels decrease significantly at ground level.” The complex chemical reactions that take place on the snow crystal’s surface cause the release of chemicals that reduce ozone at ground level. “How fast these reactions occur is partially limited by the snow crystals’ surface area,” he said. His findings are published in the journal Atmospheric Chemistry and Physics.

The Trip of a Drip

The concept of evaporation is generally understood by students in grades 5-8, but they may be unsure of the journey that a single drop of water takes from the sky to earth and back again. The National Science Education Standards stress that the process of condensation requires extensive observation and instruction if students are to really understand the water cycle.
We believe these three interactive sites will help your students visualize and understand the global water cycle.

Observe a Raindrop Traveling Through Various Paths of the Water Cycle
By clicking on arrows, students can move a raindrop from a cloud through different paths in the water cycle. The activity names the processes and supplies short definitions. Precipitation, transpiration, infiltration, runoff, and melting are among the processes represented.

Droplet and the Water CycleNSDL Annotation
This fun and challenging interactive game is from the NASA Earth Science Enterprise For Kids Only web site. Using Flash animation, students control a droplet of water falling from the sky on its journey through a rainforest, into a river, and on to the ocean, while avoiding dangers, like butterflies and insects that are very thirsty.

The Water CycleNSDL Annotation
Using this short module from the Environmental Protection Agency, students can learn about aquifers, transpiration, and condensation. This is a good web site for helping middle school students grasp the connections between different forms of water.

We Need Your Help

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? We invite you to share with us and other readers by posting your comments. Please check back often for our newest posts or download the RSS feed for this blog. You can also request email notification when new content is posted (see right navigation bar).

Let us know what you think and tell us how we can serve you better. We want your feedback on all of the NSDL Middle School PortalNSDL Annotation publications. Email us at msp@msteacher.org.

Swimming Pool Chemistry

Summer’s here and that means it’s time to head for that clear, cool, and refreshing pool! Did you know that children swallow at least 37 mL of pool water each day they swim for 45 minutes or more? Do you know how many microbes can fit into just 1 mL of water? A lot!

Here are a few resources to acquaint your students with some of the microbes we aim to kill with chlorine as well as the properties of chlorine. Several factors, such as pH and temperature, affect its activity. Due to its noxious quality, hands-on activities with chlorine are not possible. However, you and your students might want to model and simulate the chemical activity of chlorine. Or, you and your students could create case studies in small groups to trade and analyze using their new knowledge.

CDC: Healthy Swimming
The What? Where? Why? How? and Who? of recreational water illnesses (RWI).

Internet Scout Report for Physical Science: Chlorine
A list of several related web sites. We suggest Chlorine Chemistry, which presents 10 chlorine chemistry questions. Answers do not appear on the same screen, giving students a chance to think about them. The Question of the Day links to How Does Chlorine Bleach Work?. Scroll down and click on How Does Chorine Work to Clean Swimming Pools?

Chlorine
This engagingly written, one-page article provides a brief history of humans’ use of chlorine and highlights some common, useful compounds of chlorine, expanding student conceptions beyond pool water disinfectants. This article is from Chemical & Engineering News accessed through the American Chemical Society.

We Want Your Feedback
We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? We invite you to share with us and other readers by posting your comments. Please check back often for our newest posts or download the RSS feed for this blog. Let us know what you think and tell us how we can serve you better. We appreciate your feedback on all of our Middle School Portal 2 publications. You can also email us at msp@msteacher.org. Post updated 4/09/2012.