Guide to the Human Body Systems

The human body is comprised of several different systems. They work together to ensure that you can move, eat, and breathe. Each system has its own set of parts, each one with a different job. Learning more about some of the different human body systems means learning more about how you work and what is going on inside your own body every day.

Circulatory System

A Kid’s Guide to the Circulatory System: Learn words that describe this part of the body and fun facts about the human body as a whole.

Circulatory System: The Life Pump: It’s important that this system of the body pumps blood to ensure that it reaches every part of the body.

Circulation Station: Check out this interactive site that allows you to take a closer look at “the body’s superhighway.”

The Heart and its Parts: Diagrams here will help you get a closer look at the heart, including the valves and the blood vessels.

Respiratory System

Your Respiratory System: This article provides lots of information on how the respiratory system works along with a diagram of the different parts.

Clean Air, Healthy Children: A Teacher’s Guide and Activities for Young Children (PDF): In addition to useful information about the respiratory system, this document tells how air pollution can affect your body and cause problems.

How the Body Uses O2: Where does oxygen go once it heads into the lungs? Learn more about what happens to the oxygen and how it travels through the body.

Your Lungs: Full of pictures, vocabulary words, and information, this site helps you understand how your lungs work and explains more about asthma, an illness that makes it hard for your lungs to work properly, and what it feels like.

Immune System

Bodily Defenses: Close-up pictures of lymph nodes, which help the immune system do its job, can help you understand how this system works and what it does to take care of the body.

Your Immune System: Learn more about the “good guys” in your body, the “bad guys” they fight, and how the system as a whole works to keep you healthy.

What Causes Disease? How Does the Immune System Protect the Body from Disease? (PDF): This fourth-grade lesson plan offers vocabulary, charts, and activities to help kids understand this part of the body.

Teacher Resource Packet for the Immune System (PDF): Teachers can use this document to find lots of resources to help students understand the immune system.

Skeletal System

• Skeletal System Photos and Diagrams: This site offers lots of detailed photos and diagrams that look at this part of the human body. Take the quiz to see just how much you know.
• Living Bones, Strong Bones (PDF): NASA helps students take a closer look at bones with this lesson plan, which looks at what happens to astronauts’ bones in space and why strong bones matter.
• “Them Not-So-Dry Bones”: Watch this Schoolhouse Rock! video to learn about your bones.
• Help Mr. Bones! (PDF): Print this out and put the skeletal system back together.

Excretory System

Just like taking the trash out when it is full, the human body also has a process for getting rid of waste. While the teeth may be one of the first things that come into contact with food, they certainly aren’t the last. Getting rid of waste is actually a very important part of keeping the body healthy, and that’s what the excretory system does.

• Human Excretory System (PDF): These workbook pages offer a diagram of the system, an explanation of each of the parts, and questions for kids to consider.
• Worksheets on the Excretory System (PDF): From vocabulary activities to fill-in-the-blank sentences, you can learn more about the excretory system and the urinary system with these activities. You can also build a kidney to learn about and show how it works.
• The Excretory System (slide show): With lots of information along with a diagram, this slide show offers an easy-to-understand explanation of how the system works.
• Why Is Excretion Necessary for Life? Learn about waste needs to be removed from the body and how it happens.

Urinary System

The urinary system gives the body another way to get rid of waste. Made up of organs including the kidneys and the bladder, the urinary system helps the body to get rid of water and other things that it the body doesn’t need. If this part of the body isn’t working, it could cause a buildup of waste that could make you sick.

• Urinary System Diagram: Take this quiz to see if you can label all of the parts of the urinary system.
• Learn the Functions of the Human Body’s Urinary System (PDF): This lesson plan looks at the major organs of the excretory and urinary systems and helps students build a urinary system themselves.
• Urinary/Excretory System Lesson Plan: Teachers can use this lesson to help kids learn about the kidneys, what they do for the body, and how they help the body make urine.
• How Does the Urinary System Work? Check out this diagram and explanation of the different parts that all work together to form the urinary system.

Muscular System

If you are moving, your muscles are working. The muscular system uses skeletal, smooth, and cardiac muscles to take care of the body. Lots of the organs involved in the other systems are actually muscles! Whether you are breathing, running, or even digesting food, the muscular system is getting the job done.

• The Muscles Required to Run: This diagram shows two bodies and all of their muscles, how they are attached, and how they move.
• Muscle Tissue: Check out these slides that show different types of muscles that are found in the human body.
• The Muscular System (PDF): Learn about three types of muscles and their different functions with this lesson plan. At the end of the lesson, students can build a clay muscle chart.
• What Is the Strongest Muscle in the Human Body? This question doesn’t have one simple answer, but you can learn a lot about some of the muscles that work the hardest here.

Endocrine System

There are lots of glands that make up the endocrine system. This system helps you grow and even has an effect on your mood and how you sleep. Many of the parts have interesting names, like the hypothalamus and the thyroid, and they all use different chemicals inside of your body to do their jobs. Without these parts, the body wouldn’t be able to do lots of important things, including turning you from a kid into an adult.

• The Endocrine System: An Influential Part of the Human Body (PDF): Every cell and organ of the body depends on the endocrine system to regulate important things like your mood, development, and even how the rest of your body functions. This diagram shows the different parts of the system.
• The Endocrine System: Who Is in Control Here? (PDF): Glands and hormones work inside the human body in a variety of different ways. This lesson helps students understand the science behind things like emotions and puberty.
• Introduction to the Endocrine System: Check out this video that discusses the endocrine system and the types of hormones in the body.
• Endocrine Disorders Activity: What happens when the endocrine system isn’t working properly? After learning more about a patient, you can diagnose the problem, learning more about the system as a whole along the way.