In 1827, Robert Brown noticed pollen suspended in water bouncing around erratically. It wasn't until 1905 that Albert Einstein provided an acceptable explanation of the phenomenon (Kac 1947): Brownian motion is the random movement of particles (e.g., pollen) in a fluid (liquid or gas) as a result of collisions with atoms and molecules. Movement of…

Polychlorinated biphenyls (PCBs) are a family of synthetic chemicals consisting of carbon, hydrogen, and chlorine atoms. PCBs have been produced commercially since 1929 in hundreds of industrial applications. Their continued production in the United States was phased out in the late 1970s, and strict disposal guidelines were regulated as adverse…

In classroom science laboratories, unlike a real science laboratory, the teacher can guide students away from potential dead ends and toward data that are most likely to result in accurate conclusions. Sometimes, though, allowing students to pursue dead ends and to collect "bad" data can provide especially rich learning opportunities.…

Mobile devices have become a popular form of education technology, but little attention has been paid to the use of their sensors for data collection and analysis. This article describes some of the benefits of using mobile devices this way and presents five challenges to help students overcome common misconceptions about force and motion. The…

Genetic engineering is taught in biology--but as a scientific tool and not as a means to explore engineering design. Yet, given the clever behaviors and patterns that can be found when examining living systems, biology classes seem well positioned to teach foundational engineering design principles (Kuldell 2007). This article examines a new,…

Nowadays, there are lots of digital resources available to teachers. Tools such as Teachers' Domain, an online digital library (see "On the web"); interactive whiteboards; computer projection devices; laptop carts; and robust wireless internet services make it easy for teachers to use technology in the classroom. In fact, in one…

Since 2002, the PhET Interactive Simulations project at the University of Colorado has been working to provide learning tools for students and teachers. The project has developed over 85 interactive simulations--or sims--for teaching and learning science. Although these sims can be used in a variety of ways, they are specifically designed to make…

Science educators are often among the first to use emerging technologies in the classroom and laboratory. For the technologically savvy science teacher, the handheld computer is a terrific tool. A handheld computer is a portable electronic device that helps organize (via calendars, contact lists, to-do lists) and integrate electronic data…