This detailed chemistry lesson from the U.S. Department of Energy focuses on transforming vegetable oil into biodiesel through a process of transesterification. The process described offers a good model for many chemical reaction processes that are used to produce a viable product.

This short, engaging video created by NASA presents a complex topic via a simple analogy. The idea of positive and negative feedback is demonstrated by Daisyworld - a world with black and white flowers growing on it.

This PBS video focuses on sea level rise in Norfolk, Virginia and how the residents are managing the logistical, financial and political implications. Science journalists who have been studying Norfolk's rising sea level problems are interviewed, as well as local residents who are being impacted.

Students take a Home Energy Quiz from the Energy Star Program to identify home improvements that could make their homes more energy efficient. The resource includes follow-up information about energy-saving activities to reduce the cost of heating and cooling, supporting the student examination of energy use, energy efficiency and conservation.

This video, from the US Department of Energy, shows the basics of how a PV panel converts light radiated from the sun into usable power, whether on the electric grid or off, and without emissions or the use of fossil fuels.

This visualization presents a collection of sea ice data taken over a period of 34 years. Selected data can be animated to show changes in sea ice extent over time. Data is added by the National Snow and Ice Data Center as it becomes available.

In this activity, students will determine the environmental effects of existing cars and a fleet consisting of their dream cars. They compute how many tons of heat-trapping gases are produced each year, how much it costs to fuel the cars, and related information. Then, students research and prepare a report about greener transportation choices.

This animated slideshow introduces biodiesel as a fuel alternative. With concern about the use of petroleum-based fuels at an all-time high, biodiesel is experiencing a popularity surge. And algaeâotherwise known to some as pond scumâ are grabbing headlines as the next potential biodiesel superstar. But how and why do algae make oil? And why do they make so much of it? In this audio slide show, U.C. Berkeley's Kris Niyogi describes the process and its potential.

This video segment features subsistence fishing and harvesting in the Northwest US. Segment was adapted from a student video produced at Northwest Indian College in Bellingham, Washington.

In this activity, students learn about how climate change is affecting the Arctic ecosystem and then investigate how this change is impacting polar bear populations. Students analyze maps of Arctic sea ice, temperature graphs, and polar bear population data to answer questions about the impact of climate change on the Arctic ecosystem.