3rd Grade Science

3rd Grade Science Lessons & Study Guide

Explore 3rd Grade Science study guide content from the production AIPH content model.

Basic Concepts

In a nutshell: Ecosystems are communities where living and nonliving things interact and depend on each other.

## What is an Ecosystem? An ecosystem is a community of living things—like plants, animals, and tiny microbes—interacting with each other and with their environment. Ecosystems can be as big as a forest or as small as a puddle! ## Living and Nonliving Parts - **Living parts:** Plants, animals, fungi, and bacteria. - **Nonliving parts:** Sunlight, water, rocks, soil, and air. All of these work together to create a balanced system where each part depends on the others. ## Observing Ecosystems You can observe ecosystems right in your own backyard or local park. Watch how ants build their homes, or see how birds use trees for shelter. ## Why Ecosystems Matter Ecosystems provide us with food, clean air, and water. They help control the climate and even decompose waste! ### Try This! - Take a walk and list all the living and nonliving things you see. - Make a mini-ecosystem in a jar using soil, a small plant, and a little water.

Examples

  • A pond is home to fish, frogs, plants, and insects, all interacting together.
  • A fallen log in the forest provides shelter for bugs, fungi, and small animals.

Key terms

Ecosystem
A community of living and nonliving things that work together.
Habitat
The natural home of a plant or animal.
Organism
A living thing, like a plant, animal, or microbe.