One recent morning, I sat in the window seat on a flight home from foggy Atlanta, Georgia, to Maine. As we gained speed heading down the runway, I watched the wing and noted the fully extended flaps. As soon as we lifted off and entered the fog layer some 20 feet up, an intense cloud rolled off the upper surface of the wing. When I saw this phenomenon in action, I immediately thought, "A-ha! Bernoulli's principle!"
The shape of an airfoil (especially when the flaps are extended to exaggerate the airfoil) is such that the air moving across its upper surface has to go a greater distance, and, therefore, faster. This creates a reduction in the air pressure on the upper surface, and allows the relatively greater pressure below the wing to lift the plane into the air.
The roiling cloud I witnessed was the moisture being squeezed out of the damp, foggy air moving across the top of the airfoil and becoming compressed like a sponge, thus leaving less room for water molecules. It was fascinating to see it happen, and even better that I could recall my understanding of Bernoulli's principle -- something I had not thought about in years.
Like the real-world example above, following are a few of my favorite Web-based resources to help teachers explain -- and get their students to understand -- complex topics in new ways:
- Learningscience.org provides a comprehensive collection of tools for teaching science. The site offers several areas to visit, and specific tools for each are organized by grade level. Learningscience.org is a collaborative project of the Central Bucks School District, in Doylestown, Pennsylvania, including curriculum coordinator George Mehler and district teachers, and the College of Education at Philadelphia's Temple University. Don't miss the Tools of Science section!
- From the Maine Mathematics and Science Alliance, PRISMS (Phenomena and Representations for the Instruction of Science in Middle Schools) is a resource, as the site states, of "reviewed phenomena and representations" for middle school teachers and students. Another great collection of science visualizations!
- Utah State University's National Library of Virtual Manipulatives offers classic classroom materials such as tangrams, geoboards, and more. Check out the Algebra Balance Scales, for grades 6-8 and 9-12. I've had so many teachers tell me, "If only I had had this resource when I was in school!"
- CSERD (Computational Science Education Reference Desk), a Pathways project of the National Science Digital Library, brings us Project Interactivate and its collection of middle school-based mathematics tools. Be sure to check out the Discussions -- they're like a reader's theater for math!
- The Visuwords online graphical dictionary uses Princeton University's WordNet, an open source database created by university students and language researchers. You have to play around on this site to learn how to maximize what it offers. It is color coded; floating your cursor over any word delivers a definition. How about asking students to put their vocabulary words in and see what comes up?
- Ricci Adams's Musictheory.net gets you started with a choice of Lessons, Trainers, or Utilities. I'm not a musician (just ask my family), but I like the way this site helps me better understand the language of music. Check out the pop-up piano!
- Playing with Time takes a look at how the world changes over a given period. This collaboration between Red Hill Studios and the Science Museum of Minnesota allows you to view time sped up and slowed down, and offers activities and collaborative projects that illustrate just how complex time really is.
- Powers of Ten, from the Eames Office (a gallery and store devoted to the works of designers Charles and Ray Eames), is where you'll find the classic Powers of 10 film and so much more to help teachers and students alike better understand scientific notation. (That whole exponential-growth thing can be a real head-shaker!)
- NetLogo, developed by Northwestern University computer scientist Uri Wilensky, is a great free, downloadable tool for visualizing complexities -- everything from forest fires and predator-prey relationships to HIV.
I'd be interested to know what you think of these sites, and if you know of others, please share!