Grade 6 · Science · Lesson 22

Microbes: helpful vs harmful

Microbes are tiny living things — so small that you need a microscope to see them. They live everywhere: in the soil, in the air, in the ocean, on your skin, and even inside your gut right now. People often think of microbes as "germs" that make us sick, but the truth is that the vast majority of microbes are helpful, harmless, or even necessary for life on Earth. Only a small minority are harmful pathogens that cause disease.

What this lesson teaches

1Define a microbe as a living thing too small to see without a microscope
2Name the four main kinds of microbes — bacteria, viruses, fungi, protists
3Give examples of helpful microbes that work for people, food, and soil
4Sort common microbes into helpful and harmful based on what they do

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