Open-and-go lessons that inspire kids to love science.

Science curriculum for K—5th grades.

90 sec
  • Hands-on — lead students in the doing of science and engineering.
  • Standards-aligned science lessons — Cover core standards in 1-2 hours of science per week.
  • Less prep, more learning — prep in minutes not hours. Captivate your students with short videos and discussion questions.

Sign up now to try Mystery Science for free.

Sign up

Learn more

Open-and-go lessons that inspire kids to love science.

Sign up now for tons of free lessons like this one!

Back

Mini-lessons

Video Bonus Vote
Full Screen
Controls Icon Exit Full Screen
Video trouble?
Slide Image
Full Screen
Controls Icon Exit Full Screen
Full Screen
Controls Icon Exit Full Screen
Video trouble?
Full Screen
Controls Icon Exit Full Screen
Slide Image
Full Screen
Controls Icon Exit Full Screen
Full Screen
Controls Icon Exit Full Screen
Video trouble?
You probably know that fireflies (lightning bugs) flash light! Why though? Do you think their light helps them somehow?
5
Full Screen
Controls Icon Exit Full Screen
Video trouble?
They light up so they can find each other from far away. Imagine being a tiny bug and trying to find another bug!
5
Full Screen
Controls Icon Exit Full Screen
Video trouble?
Some fireflies flash all at the same time. Scientists used flashlights to flash patterns—and the fireflies copied the flashes!
5
Full Screen
Controls Icon Exit Full Screen
Video trouble?
Full Screen
Controls Icon Exit Full Screen
Video trouble?
Slide Image
Creatures that light up are rare, EXCEPT in one of these habitats. Which habitat do you think has a lot of this type of creature? Why?
4
Full Screen
Controls Icon Exit Full Screen
Hint: Think of fireflies. They only come out at night in the DARK, using light to find each other. Does this give you any ideas?
4
Full Screen
Controls Icon Exit Full Screen
Video trouble?
The DEEPEST parts of the ocean are so dark and almost no light reaches there. The only way to see creatures is if they light up!
4
Full Screen
Controls Icon Exit Full Screen
Video trouble?
Full Screen
Controls Icon Exit Full Screen
Video trouble?
Is this little fish breathing fire? Is it spitting out light? What do you think is going on here?
3
Full Screen
Controls Icon Exit Full Screen
Video trouble?
It’s spitting out the meal it just ate! The fish isn’t glowing—its food is glowing! Why would it want to get rid of a glowing meal?
3
Full Screen
Controls Icon Exit Full Screen
Video trouble?
Slide Image
The dark ocean is filled with predators—fish that will eat smaller fish. If a small fish is glowing, it’s easier for predators to find it.
3
Full Screen
Controls Icon Exit Full Screen
Full Screen
Controls Icon Exit Full Screen
Video trouble?
Slide Image
This thing is crawling around in the jungle. What do you think it is?
Full Screen
Controls Icon Exit Full Screen
If you said worm, you were close—but it’s actually a beetle! Why do you think it lights up? (It’s not to find others in the dark.)
2
Full Screen
Controls Icon Exit Full Screen
Video trouble?
The lights are a warning! When predators eat these beetles, they get sick! So they learn to stay away, and the beetles stay safe!
2
Full Screen
Controls Icon Exit Full Screen
Video trouble?
Full Screen
Controls Icon Exit Full Screen
Video trouble?
Here’s another dark place! It’s a cave! What do you think it is that's glowing?
1
Full Screen
Controls Icon Exit Full Screen
Video trouble?
They’re called glowworms! Each glowworm can make sticky “string,” kind of like a spider’s web. Why do you think they glow?
1
Full Screen
Controls Icon Exit Full Screen
Video trouble?
Small bugs fly to the lights and get caught in the sticky string. Then the glowworms eat them!
1
Full Screen
Controls Icon Exit Full Screen
Video trouble?
Slide Image
Full Screen
Controls Icon Exit Full Screen
Full Screen
Controls Icon Exit Full Screen
Video trouble?

Voting for this episode is now closed. Would you like to vote on the most recent poll?

We pulled three questions from our jar. Which question do you want to explore?

  • How is cheese made?

    -Glenn, 2nd Grade

  • Why do animals have tails?

    -Eowyn, 4th Grade

  • How many stars are in the sky?

    -Danna, 3rd Grade

Why do fireflies glow?

Watch the video to discover the answer and don't forget to vote for next week's question. There are mysteries all around us. Have fun and stay curious!