Crustaceans Lesson for Kids

Instructor: Heather Pier

Heather has taught high school and college science courses, and has a master's degree in geography-climatology.

Come learn about crustaceans! A crustacean is a type of animal that can live in both freshwater and saltwater. The most well known crustaceans are crabs and lobsters.

What is a Crustacean?

Have you ever eaten crab, lobster or shrimp before? If you have, then you have seen (and eaten) a crustacean. A crustacean is a type of animal that lives in the water. Some live in freshwater and some live in saltwater.

If you have ever eaten a lobster, then you have seen a crustacean.

They can be found all over the world. Because they can be found in so many places and many people think they taste good, they are a very popular form of seafood.

Features of Crustaceans

Crustaceans are invertebrates. This means that they do not have a backbone. Instead, they have an exoskeleton to protect them. An exoskeleton is a hard, shell-like covering that protects their soft inside body parts from being crushed or injured.

As the crustacean gets bigger, it no longer fits in its exoskeleton. When it gets too big for it, it sheds it and grows a new one. It's as if you got too big for your clothes but you could magically grow new clothes instead of going to buy them.

Spiders and cockroaches have exoskeletons too. When you crack into a lobster or crab to eat it, the part you are cracking is the exoskeleton. (Spiders and cockroaches are NOT crustaceans, though.)

Where Do Crustaceans Live?

Crustaceans can be found all over the world. They can live in both freshwater and saltwater, so they can live in lakes, oceans, and rivers.

Crustaceans that live in freshwater will only ever be able to live in freshwater, and those that live in saltwater will only able to live in saltwater. If you put them into the wrong kind of water, they will die. They can be found in both warm and cold places.

All crustaceans, except for ones called barnacles, are able to move around using their legs. They can live underwater and on beaches or riversides, or sometimes in deeper water. Barnacles, on the other hand, don't have legs that they can walk on - instead, they eat with their legs! For this reason, they live their lives attached to other things.

Crustaceans can move around on the ocean or river bottom using their legs. The only crustacean that can not walk is the barnacle.

Sometimes barnacles attach to hard objects like pipes and ships. They can also attach themselves to large animals, like whales. Imagine what it would be like if you were a whale and had another animal permanently stuck to you. It would be weird, wouldn't it?

What Do Crustaceans Eat?

Crustaceans don't get to go to a grocery store to get their food like you do. Larger crustaceans usually hunt for their food. Smaller crustaceans will eat just about anything they can find.

Sometimes what they find is a plant, and other times it is the dead body of another animal. Some will also filter tiny specs of food out of the water to eat.

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create An Account