Contributor: Samantha Penna. Lesson ID: 12048

What is the biggest fish you can think of? Did you think of a whale? Surprise! Whales are not fish, although they live in the ocean! Learn more cool stuff about these big creatures and how they live!


Life Science

learning style
personality style
Grade Level
Primary (K-2)
Lesson Type
Quick Query

Lesson Plan - Get It!

Audio: Image - Button Play
Image - Lession Started Image - Button Start
  • What do you think is the biggest animal on the earth?
  • What about for all time?

Look at the image below showing the sizes of a person, a blue whale, a shark, and several dinosaurs.

large predatory dinosaur size in comparison to a human, great white shark, and blue whale

  • Would you have guessed blue whales were so big?

Whales are among the largest animals on the earth.

The blue whale is the largest whale in the ocean and can grow up to ninety-eight feet long (which is nearly two and a half buses long).

All whales are mammals. This means they are warm-blooded, breathe air, have live babies that they feed with milk, and have hair. Even when a whale swims in chilly ocean waters, its body temperature stays the same.

blue whale

All whales live in the salty waters of the ocean. Some species of whales can be found living in every ocean, but others may only be found in one or two of the earth’s oceans.

For example, sperm, killer, and blue whales live in every ocean. Gray whales, on the other hand, only live in the Pacific and Atlantic Oceans.

Because all whales are mammals, they must come up to the ocean's surface for air. A whale breathes out of a blowhole on the top of its head.

Most whales must come up for air every twenty minutes. A sperm whale can spend an hour and a half underwater without coming up for air.

Below, you can see a humpback whale coming up for air.

  • Have you ever tried to hold your breath underwater?
  • How long could you stay underwater?

whale jumping

There are two main types of whales: baleen whales and toothed whales.

Baleen whales — like the bowhead, northern right, southern right, gray, humpback, and blue whales — eat only krill and plankton. Krill and plankton are small creatures that can be found in the ocean.

The average humpback whale eats over four-thousand pounds of krill, plankton, and small fish a day!

gray whale

Toothed whales — like the sperm whale, killer whale, shepherd’s beaked whale, and the spade-toothed whale — hunt for their food. They search out their prey and capture it with their strong teeth.

They usually eat fish, crabs, starfish, squids, seals, and other sea creatures. Once they capture their prey, they swallow their prey whole!

Below is a picture of an Orca, also known as a killer whale.


Whales, like all mammals, give birth to live babies. Once their babies are born, they feed their babies milk.

Most female whales give birth every two or three years. One baby whale is born at a time, but sometimes two are born, which is rare.

Once the baby whale is born, the mother brings it to the surface to breathe fresh air. The mother whale will take care of the baby until the baby can swim to the surface for air and feed (or hunt, depending on the whale).

humpback whales

  • Did you know most whales are endangered species?

This means few of them are left in the ocean.

Head to the Got It? section to learn about endangered whales and how you can help!

Image - Button Next