Inside an Earthworm: Amazing Facts Every Curious Child Will Want to Know

July 9, 2026

One of the best parts of exploring nature with young children is listening to their questions. Children are naturally curious about how animals work. Instead of simply giving them the answers, encourage them to look closely, make predictions, and wonder together.

You do not have to know everything. Sometimes discovering the answers together is the best part of learning. Let's take a closer look inside an earthworm!

What Is an Earthworm?

An earthworm is an invertebrate, which means it is an animal without a backbone. Earthworms belong to a group of segmented worms called annelids. If you look closely, you will notice that an earthworm's body is made up of many small rings called segments.

Earthworms spend most of their lives underground, where they feed on dead leaves and other decaying plant material. As they tunnel through the soil, they help forests, gardens, and parks stay healthy by improving the soil.

Is an Earthworm an Insect?

No. Although many children call every small animal a bug, earthworms are not insects.

An insect has:

Six legs
Three body sections
Two antennae
A hard outer skeleton

Earthworms do not have any of these features. Instead, they have a long, soft body with no legs and no hard outer shell.

Try This Together

Ask your child, "Can you find six legs on the earthworm?"

This simple comparison helps children begin noticing how different animals are built.

Is an Earthworm a Bug?

Not scientifically. Many people use the word bug to describe almost any small creature they find outdoors. Scientists use the word bug much more specifically. True bugs belong to a group of insects called Hemiptera.

Earthworms belong to a completely different group of animals called annelids. So while someone may casually call an earthworm a bug, it is not actually a bug.

Does an Earthworm Have Eyes?

No. Earthworms do not have eyes like people or birds. Instead, they have special light sensitive cells in their skin, especially near the front of their bodies. These cells allow them to tell the difference between light and darkness. That is why earthworms quickly move away from bright sunlight and spend most of their lives underground.

Ask Your Child: "Why do you think worms like dark places?"

Does an Earthworm Have a Brain?

Yes. An earthworm has a very small brain called a cerebral ganglion located near the front of its body. Although it is much simpler than a human brain, it helps control movement and respond to changes in the environment. A long nerve cord runs through the body, carrying messages between the brain and the rest of the worm.

Does an Earthworm Have Teeth?

No. Earthworms have no teeth. Instead of chewing, they swallow tiny pieces of dead leaves, decaying plants, fungi, and soil. Inside their bodies is a muscular organ called the gizzard.

Tiny grains of sand and soil inside the gizzard grind the food into smaller pieces, much like our teeth chew food.

Does an Earthworm Have Bones?

No. Earthworms have no bones and no skeleton. Instead, their bodies are supported by muscles and fluid inside their body cavity. This flexible body allows them to squeeze through tiny spaces in the soil that animals with bones could never fit through.

Does an Earthworm Have Lungs?

No. Earthworms breathe through their skin. Their skin must stay moist so oxygen from the air can dissolve into the thin layer of moisture covering their body. That oxygen then passes directly into their blood. If an earthworm dries out, it cannot breathe properly.

Does an Earthworm Have Ears?

No. Earthworms do not have ears. Instead, they sense vibrations moving through the soil.

These vibrations help them detect danger, such as digging moles or birds searching for food.

Does an Earthworm Have a Nose?

No. Earthworms do not have a nose like people. Instead, they use special sensory cells in their skin and around their mouth to detect chemicals in the soil. These help them find food and respond to their surroundings.

Does an Earthworm Have a Mouth?

Yes. An earthworm has a small mouth at the front end of its body. It uses this mouth to swallow soil and tiny pieces of decaying plants. Its mouth is much too small to bite people.

How Many Hearts Does an Earthworm Have?

This is one of children's favorite questions. Earthworms have five pairs of muscular aortic arches, often called five hearts because they pump blood through the body.

Unlike our single heart, these muscular arches work together to keep blood moving. Earthworm blood is red because it contains hemoglobin, just like human blood. The difference is that an earthworm's hemoglobin is dissolved directly in the blood rather than carried inside red blood cells.

How Do You Know Where the Earthworm’s Head Is?

An earthworm does not have a head like a person or an insect, but it does have a front end.

The front end is usually the end that moves forward first. It is also the end with the mouth.

One helpful clue is the clitellum, the thicker band around an adult earthworm’s body. The head is usually on the shorter side of the worm, closer to the clitellum.

You can also watch how the earthworm moves. The front end often stretches forward first, then the rest of the body follows.

Ask your child:

Which end is leading?
Which end stretches first?
Can you find the thicker band?
Is the head closer to the short side or the long side?

What to Notice Together

The next time your child finds an earthworm, encourage them to become a scientist.

-Can you find the head?

-Can you see the tiny rings covering its body?

-Can you find the thicker band around the middle?

-Does it move away from the sunlight?

-Can you watch it disappear underground?

Every careful observation helps children build the habit of slowing down and truly noticing the natural world.

Remember

Children do not need to memorize every part of an earthworm. The goal to raise children who ask questions, observe carefully, and become excited to discover the answers. That curiosity often lasts much longer than any science lesson.

Continue the Adventure Outdoors

Reading about earthworms is a wonderful beginning. Watching one move through the soil, noticing its tiny body segments, feeling how it moves, and asking questions together creates a much deeper understanding.

Every visit to a local park is an opportunity to discover something new. The more children observe the plants, insects, and animals around them, the more confident, curious, and connected they become to the natural world.

If you would like to continue exploring the nature of Long Island together, we would love to have you join us on the trail.

About Little Hikers Long Island

Little Hikers Long Island is a fully outdoor parent and child nature program at West Hills County Park in Huntington, New York. Through hands-on exploration, families learn about the local plants, insects, animals, and seasonal changes found right here on Long Island. Children learn to observe closely, ask thoughtful questions, compare what they see, and build a lasting relationship with the natural world around them.

Our goal is to help children become careful observers, confident explorers, and future stewards of the places they call home, because children protect what they understand.

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