Prior to reaching households, water is exposed to a variety of treatments designed to render it fit for human consumption and use. One of the first treatment steps is the removal of suspended solids using chemical additives called flocculants. In this activity, students learn about two commonly used flocculants and clean water collected from a local pond or river. They experiment with flocculant, stirring and pH variables.

Learners will read or listen to a story about two sisters, Marisol and Sofia, as they explore the Sun's role in the water cycle. Additionally, numerous extension resources are included in the accompanying educator guide, such as suggestions for no-cost language arts activities, links to further science activities, a book walk cue chart to guide classroom discussion before, during, and after the story, a graphic organizer, and alignments to the National Science Education Standards (NSES) and the Next Generation Science Standards (NGSS).

Examine how the human/grizzly relationship has changed since the closing of the Yellowstone dumps, and also learn about the challenges posed to both humans and bears, in this video segment from Nature.

This video from NASA explains the process by which gamma-ray flashes associated with storms produce matter/antimatter particle pairs.

This web-based activity tackles the broad reasons for undertaking ocean exploration - studying the interconnected issues of climate change, ocean health, energy and human health. Students examine the types of technology ocean scientists use to collect important data.

Students reenact a public hearing to determine how to manage a deer herd that is overpopulated.

This short animated video provides a general overview of the atmosphere, carbon dioxide, and the greenhouse effect.

Ranks all 50 states in total energy production. Includes links to tables which rank production of crude oil, natural gas, coal, and electricity; crude oil emissions; total energy consumption; and energy prices.

This video shows some of the most dramatic fluctuations to our cryosphere in recent years, using visuals created with a variety of satellite-based data.

This video describes the role that dendrochronology plays in understanding climate change, especially changes to high elevation environments at an upper tree line. Dendrochronologists from the Big Sky Institute sample living and dead trees, describe how correlations between trees are made, and explain how tree cores record climate changes.

This fun Web site is part of OLogy, where kids can collect virtual trading cards and create projects with them. Here, they explore the Tree of Life cladogram. The site begins with a brief explanation of cladograms and how the Tree of Life shows the relationship of all living things on Earth. A cladogram of fruit is used to demonstrate on a small scale how scientists use this tool to understand how things are similar and different. A portion of the Tree of Life cladogram is included, showing true bacteria, arthropods, mammals, and 11 other important groups of species. Students can mouse over the branching points to see what the subsets have in common. The site also includes a pie chart view that compares the relative size of the most important groups of species. Students can click on each group to learn its characteristics, known species, size range, and other important details.

This activity describes the flow of carbon in the environment and focuses on how much carbon is stored in trees. It goes on to have students analyze data and make calculations about the amount of carbon stored in a set of trees at three sites in a wooded area that were to be cut down to build a college dormitory.

This issue of the free online magazine, Beyond Penguins and Polar Bears, explores the tundra and how it can illustrate ecological concepts, relationships, and changes.

This nonfiction article, written for students in grades 4-5, explores the relationships between various tundra species: marsh marigolds, bot flies, and caribou. Modified versions are available for students in younger grades.

This article assembles free resources from the Tundra: Life in the Polar Extremes issue of the Beyond Penguins and Polar Bears cyberzine into a unit outline based on the 5E learning cycle framework. Outlines are provided for Grades K-2 and 3-5.

This video discusses how methane digesters turn waste from dairy cows, food garbage, and other organic matter into usable gases and other fuels.

This is a two part journaling activity prior to an existing week long biology field lab. The journaling activities described here have been added to the beginning of the Pond Study Lab to enhance student learning of observation and quality journaling skills.

The United Nations Educational, Scientific and Cultural Organization (UNESCO) sponsors a collection of online resources for training in environmental topics. These resources are organized by topic (agriculture, energy, human health, and others) and are searchable by keyword. Each resource is accompanied by a brief metadata description and is provided in a choice of formats: downloadable (PDF), XML, or a bookmark.

This visualization is a website with an interactive calculator that allows for estimation of greenhouse gas production from croplands in the United States.