Summer 2026 Science Updates: Where did the old lessons go? What was the old unit lesson order? – Mystery Science

Already bought the supplies for an old lesson? Don’t worry, we saved you the link for now.

We’re always incorporating great teacher feedback to make our lessons more engaging, easier to prep, and more aligned to the latest best pedagogical practices, so we encourage you to check out the updated versions as soon as you can!

Scroll down to see the lesson order for each updated unit.

Grade K

Pushes & Pulls Unit

Updated?	Lesson	Title/Link
No	Lesson 1	What’s the biggest excavator?
No	Lesson 2	Why do builders need so many big machines? (Read-Along)
Yes	Lesson 3	How can you knock down a wall made of concrete?
No	Lesson 4	How can you knock down the most bowling pins? (Read-Along)
No	Lesson 5	How can we protect a mountain town from falling rocks?
No	Lesson 6	How could you invent a trap? (Read-Along)

Grade 1

Animal Traits & Survival Unit

Updated?	Lesson	Title/Link
No	Lesson 1	How can you help a lost baby animal find its parents?
No	Lesson 2	Can you predict what an animal’s babies will look like?
Yes	Lesson 3	Why do baby ducks follow their mother? (Read-Along)
No	Lesson 4	Why do birds have beaks?
No	Lesson 5	Why are polar bears white?

Grade 2

Plant Growth & Interactions Unit

Updated?	Lesson	Title/Link
No	Lesson 1	How did a tree travel halfway around the world?
No	Lesson 2	Why do seeds have so many different shapes?
No	Lesson 4	Could a plant survive without light?
No	Lesson 5	How much water should you give a plant?

Grade 3

Heredity, Survival, & Selection Unit

Updated?	Lesson	Title/Link
No	Lesson 1	How do you identify a mysterious fruit?
No	Lesson 2	What do dogs and pigeons have in common?
No	Lesson 3	How could a lizard’s toes help it survive?
Yes	Lesson 4	Why do dogs wag their tails?
No	Lesson 5	How long can people (and animals) survive in outer space?

Grade 4

Earth's Features & Processes Unit

Updated?	Lesson	Title/Link
No	Lesson 1	Could a volcano pop up where you live?
No	Lesson 2	Why do some volcanoes explode?
No	Lesson 3	Will a mountain last forever?
No	Lesson 4	What did your town look like 100 million years ago?
Yes	Lesson 5	How could you survive a landslide?

Grade 5

Ecosystems & The Food Web Unit

Updated?	Lesson	Title/Link
No	Lesson 1	What if all the ants disappeared?
No	Lesson 2	How does a tiny seed become one of the heaviest trees on Earth?
No	Lesson 3	Where do fallen leaves go?
No	Lesson 4	Do worms really eat dirt?
Yes	Lesson 5	Why do you have to clean a fish tank, but not a pond?
No	Lesson 6	How can we protect Earth’s environments?
No	Lesson 7	Why did the dinosaurs go extinct?

Chemical Reactions & Properties of Matter Unit

Updated?	Lesson	Title/Link
Yes	Lesson 1	Are magic potions real?
Yes	Lesson 2	Could you transform something worthless into gold?
Yes	Lesson 3	What would happen if you drank a glass of acid?
No	Lesson 4	What do fireworks, rubber, and Silly Putty have in common?
Yes	Lesson 5	Why do some things explode?