NatureServe Explorer
This site from NatureServe has information on more than 70,000 plants, animals, and ecosystems of the United States and Canada. A companion site, InfoNatura, has information about species in Latin America. You can search by name, taxonomy, location, or conservation status. For some species you'll find detailed information, including images.
Intended Audience: General Reading Level: Middle/High School Teacher Section: No Searchable: Yes

Encyclopedia of Life
This site is an effort to become an online reference source and database for every one of the 1.8 million species that are named and known on the planet. You'll find species profiles, data, distribution maps and more.
Intended Audience: General Reading Level: Middle/High School Teacher Section: Yes Searchable: Yes

The Tree of Life
This collaborative effort of biologists and nature enthusiasts from around the world provides information about biodiversity, the characteristics of different groups of organisms, and their evolutionary history. A special section of the site, Treehouses, is designed for younger students.
Intended Audience: General Reading Level: High School Teacher Section: Yes Searchable: Yes

EarthPulse
Keep tabs on the health and vitality of the planet at this site from National Geographic. Sections on the Ocean, Climate, Population, Land, Wild Species, Ecosystems, and Energy include online activities and articles that will help you explore topics like tornados, rivers,overpopulation, and conservation.
Intended Audience: General Reading Level: Middle School Teacher Section: No Searchable: No

One World Journeys
Discover the natural wonders of the world at this site that features online expeditions that focus on wildlife, natural resources, and cultures. Take an expedition to Florida's springs and learn about the manatee, travel to Tanzania and learn about Jane Goodall's work with chimpanzees, learn about the cougar and the threats it faces, dive down into the Palmyra Atoll and explore life in a coral reef, travel upstream with the Pacific salmon, or take a trip to the Sonoran Desert and discover the secrets of one of the worlds most biologically diverse ecosystems.
Intended Audience: General Reading Level: Middle School Teacher Section: Yes Searchable: No

Environmental Kids Club
This site from the EPA explores air, water, garbage and recycling, and plants and animals.
Intended Audience: Students Reading Level: Elementary School Teacher Section: Yes Searchable: Yes

Environmental Student Center
This site from the EPA explores air, water, and the land and features games and activities.
Intended Audience: Students Reading Level: Middle School Teacher Section: Yes Searchable: Yes

High School Environmental Center
This site from the EPA explores air, water, waste and recycling, conservation, ecosystems, and health and safety.
Intended Audience: Students Reading Level: High School Teacher Section: Yes Searchable: Yes

What's It Like Where You Live
Learn about biomes and the plants and animals that are found in them at this site from the Missouri Botanical Garden.
Intended Audience: Students Reading Level: Elementary/Middle School Teacher Section: No Searchable: No

EcoKids
This site from Earth Day Canada has lots of games, activities, and information about the environment. You'll find sections on climate change, pollution, waste, energy, water, conservation, and more. Check out the Eco Fact of the Day, open up the Eco Calendar, find neat environmental facts for every day of the year, or read the feature of the week.
Intended Audience: Students Reading Level: Elementary/Middle School Teacher Section: Yes Searchable: Yes

Global Warming
Is it getting hot in here? Check out this site on global warming and climate change from the EPA. You'll find information, games, animations, and links to other sites.
Intended Audience: Students Reading Level: Elementary/Middle School Teacher Section: Yes Searchable: No

Garbage
Learn how you and your community can reduce waste at this site from Annenberg/CPB.
Intended Audience: Students Reading Level: Middle School Teacher Section: No Searchable: No

Envirolink
This site has links to thousands of environmental resources on the Web as well as news headlines and an interactive map of US-based environmental resources.
Intended Audience: General Reading Level: Middle School Teacher Section: No Searchable: Yes

EE Link
This site from the North American Association for Environmental Education features resources for teachers and students including a section on endangered species.
Intended Audience: Teachers Reading Level: N/A Teacher Section: N/A Searchable: Yes

Kids Do Ecology
This site from the National Center for Ecological Analysis and Synthesis includes sections on biomes, marine mammals, and careers in ecology.
Intended Audience: Students Reading Level: Elementary/Middle School Teacher Section: Yes Searchable: Yes

EcoNet
Learn about population, competition, cycles in nature, and biomes.
Intended Audience: General Reading Level: Middle School Teacher Section: No Searchable: No

EEK!
This site from the Wisconsin Department of Natural Resources is intended for students in grades 4-8 and explores the environment. You can learn more about habitats, plants, and animals in the Nature Notes section, explore earth systems like water and air in the Our Earth section, or learn about careers in science in the Get a job section.
Intended Audience: Students Reading Level: Elementary/Middle School Teacher Section: Yes Searchable: Yes

NatureWorks
This companion site to the series NatureWorks looks at the ecosystem, animal behavior, and animal adaptations, and has profiles of over 200 North American animals.
Intended Audience: Students/Teachers Reading Level: Elementary/Middle School Teacher Section: Yes Searchable: No