Jellyfish

Lesson Plan

• Have you ever been stung by a jellyfish at the beach?
• Have you seen a jellyfish lying on the sand?

Tell your parents or teacher what you know about jellyfish, then learn more as you read (and watch) on!

Jellyfish are found all around the world.

They can be found in every ocean. Some jellyfish live in freshwater, too!

The most commonly known freshwater jellyfish is the hydrozoan jellyfish. Common saltwater jellyfish include moon jellyfish, purple-striped jellyfish, white-spotted jellyfish, and flower hat jellyfish.

The jellyfish below are moon jellyfish:

• Did you know a jellyfish isn’t actually a fish?

Jellyfish are invertebrates. This means they don’t have a backbone. As a matter of fact, jellyfish don’t have any bones at all! Their bodies are made up of a jelly-like substance called mesoglea.

Their skin has three layers. The layer on the outside is called the epidermis. The layer in the middle is called the thick elastic. The layer all the way on the inside is called the gastro-dermis.

Most jellyfish are transparent. This means you can see through them! Some are translucent. This means light can pass through the jellyfish, but clear images can’t be seen through it.

Some jellyfish are very small and hard to see, while others — like the lion’s mane jellyfish — can have tentacles that are over 100 feet long!

• What do you notice about the jellyfish pictures below?

These are flower hat jellyfish. Describe their color and shape to a parent or teacher:

• How do you think jellyfish get around?

They don’t have legs for walking. They also don’t have brains for thinking! Tell a parent or teacher how you think jellyfish travel.

Great work!

• Did you guess that jellyfish simply float along the ocean currents and use their tentacles to swim?

• How do you think jellyfish protect themselves?

Tell a parent or teacher.

Jellyfish protect themselves with small stinging cells found all over their tentacles. These stinging cells are used to stun and paralyze prey.

• Did you know jellyfish have a mouth?

Their mouth is hidden under the bell shape above their tentacles. Jellyfish eat crustaceans (like shrimp), plants, and fish.

Excellent work! You learned some new information about jellyfish. Tell your parents or teacher one interesting fact you learned about jellyfish, then move on to the Got It? section.