McGraw Hill
Arthropods
Are spiders related to crabs? Study the order of arthropods with a reading selection about animal diversity. It provides details about each class within the order, as well as vivid pictures and explanatory charts.
CK-12 Foundation
Ck 12: Life Science: 12.13 Terrestrial Biomes
Learn about land biomes and their ecology.
CK-12 Foundation
Ck 12: Life Science: 12.12 Biome
Learn how the biomes of the world are determined by their climate and ecosystem.
The Franklin Institute
The Franklin Institute: Treasures at Sea
Learn about ocean systems and habitats. Lots of reading, writing, games, and interactive activities. Colorful and fun.