| Title | Season | Episode # | First Aired |
|---|---|---|---|
| The Mystery of Plants | 4 | 31 | Monday January 1, 2007 |
| The Mystery of Weather | 4 | 32 | Monday January 1, 2007 |
| The Mystery of Size and Shape | 4 | 33 | Sunday October 16, 2005 |
| The Mystery of Flight | 4 | 34 | Sunday October 23, 2005 |
| The Mystery of the Five Senses | 4 | 35 | Sunday October 30, 2005 |
| The Mystery of Water | 4 | 36 | Sunday November 6, 2005 |
| The Mystery of Bugs | 4 | 37 | Saturday November 12, 2005 |
| The Mystery of Time | 4 | 38 | Saturday November 19, 2005 |
| The Mystery of Stars and Planets | 4 | 39 | Saturday November 26, 2005 |
| The Mystery of Dinosaurs | 4 | 40 | Saturday December 3, 2005 |