---
title: "Classifying Organisms"
description: "Describe how living things are classified into broad groups (micro-organisms, plants, animals) according to common observable characteristics, similarities, and differences"
canonical: https://lightmysky.com/learn/science/classifying-organisms-mt_IY3KwGLZgk
source: https://lightmysky.com/learn/science/classifying-organisms-mt_IY3KwGLZgk.md
retrieved: 2026-10-19
---

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# Classifying Organisms

Describe how living things are classified into broad groups (micro-organisms, plants, animals) according to common observable characteristics, similarities, and differences

Subject: Science · Area: Ecosystems & Habitats · Ages 10 to 11
Page: https://lightmysky.com/learn/science/classifying-organisms-mt_IY3KwGLZgk

## Ready when they can

- Name the broad classification groups: micro-organisms, plants, animals (and fungi if known)
- Describe observable characteristics used for classification (e.g. plants make own food, animals move and eat)
- Give examples of organisms in each group, including micro-organisms like bacteria

## Lesson: The Big Groups of Living Things

Scientists sort every living thing into a few big groups. To decide which group something belongs to, look at how it gets food, whether it moves on its own, and how big it is.

Plants make their own food using sunlight, and they stay rooted in one place. Animals cannot make their own food, so they move around to find and eat it. Micro-organisms are living things so small you need a microscope to see them, like bacteria.

**Example.** Look at an oak tree, a rabbit, and a drop of pond water. The oak tree stays still and makes its own food from sunlight, so it is a plant. The rabbit moves around and eats grass, so it is an animal. The pond water holds bacteria too small to see without a microscope, so they are micro-organisms.

*(drawing: Ask these questions about any living thing. Each answer points straight to its group.)*

**Tip.** Some scientists add a fourth group called fungi, like mushrooms and mold. Fungi cannot make their own food like plants. Instead, they feed by breaking down dead plants and animals.

**Recap.** Living things sort into big groups, plants, animals, and micro-organisms, based on how they get food, whether they move, and how big they are.

## Practice

24 questions on this page, each with its working shown.

## Needs first

- [Classification Keys](https://lightmysky.com/learn/science/classification-keys-mt_brgde1Vx0P)

## Opens up

- [Evidence-Based Classification](https://lightmysky.com/learn/science/evidence-based-classification-mt_B8lX8OCzGu)
- [How Natural Selection Works](https://lightmysky.com/learn/science/how-natural-selection-works-mt_FuVEZ1Ac9s)