Along came a spider, who sat down beside her. She screamed, but RJ wouldn't smash it because spiders are a limiting factor for other insects in an ecosystem. In this video, other common limiting factors for populations are listed....

Will human population growth always be exponential, or will we find a limiting factor we can't avoid? Young scientists learn about both exponential and logistic growth models in various animal populations. They use case studies to...

Brainstorm ideas to design a sustainable guest village in the Sonoran Desert. The first installment of a nine-part unit teaches young environmental scientists about the basics of the Saguaro National Park and about sustainable design....

As the reality of population decline across many species becomes real, pupils learn about the variables related to changes in populations. They complete a simulation of population changes and graph the results, then discuss limiting...

Bored with your current biome bag of tricks? This bundle is a bountiful bag of biome fun! Travel the globe with seventh graders and explore the biotic and abiotic factors that define our world's biomes. Then, introduce a little...

Psychologists study human relationships while ecologist study relationships between organisms in the environment. An introduction to ecology and the related vocabulary benefits scholars as they progress through the presentation and...

At first glance, grassland ecosystems might seem dull and uninteresting, but once you start to explore it's amazing the things you'll find! Through this series of engaging lessons, activities, and experiments, elementary students examine...

Two teams—the environmentalists and herons—play four rounds of the game, Oh Heron. Using hand symbols to represent food, shelter, and water, players locate their match to produce more herons while those unmatched decompose. 

If the Lorax were to write a letter, what would he write? Introduce your class to systems and feedback loops through the whimsical stylings of Dr. Seuss. Learners take on the Lorax's point of view to write a letter, among other activities.

Do you know the name for the biological study of interactions? A short presentation with accompanying worksheet introduces individuals to ecology. The materials offer a broad overview of the subject and the levels of organization to...