Folktale
Unit 1 From Fiction to Fact
Unit 2 Real Enough

Light
Unit 3 A Bright Idea
Unit 4 What do you see?

Trees
Unit 5 The Tree of Life
Unit 6 Not so Innocent

Competition
Unit 7 Just for Fun
Unit 8 Fame and Fortune

Unsolved Mystery
Unit 9 Forever Young?
Unit 10 A Daring Escape

Disasters
Unit 11 Sweet Disaster
Unit 12 Gone

Animals
Unit 13 Zombie Ants!
Unit 14 Why Stripes?

Origins
Unit 15 Instead of Us
Unit 16 Stuck Together

Art
Unit 17 A Self-Portrait?
Unit 18 What is Art?

Lightning
Unit 19 Human Lightning Rod
Unit 20 A Shocking Sight