Episode 1 - Raijin-Oh Arrives

Eldran piloting the mecha Raijin-Oh crash lands into Hinobori's elementary school. With the last of his powers, Eldran saves the ones in the school at the moment: class 3 of the 5th grade. He entrust them with Raijin-Oh and the duties to protect the Earth, while Eldran goes into hibernation to recover his powers.

Episode 2 - We Are the Earth Defense Class

Class 5-3 gets a visit from the army, demanding to hand over Raijin-Oh. The arguing is interruped when Jaku Beast Dustoron is running loose in the city. After finding out that only Class 5-3 can operate Raijin-Oh, the army has no choice but leave Class 5-3 alone.

Episode 3 - Tests Are a Huge Annoyance!?

The entire Class 5-3 average match score of the last test is far below the rest of the other classes and needs to do a retest. Asuka, Kouji, Maria and Tsutomu are assigned to help Jin with his studies as his test score is zero. Jin tries to run away, but in the end can't escape. The next day, right before the retest, Jaku Beast Testora appears and Class 5-3 needs to sortie. After defeating the Jaku Beast, Class 5-3 does the retest much to the dismay of Jin. A couple of days later the tests are graded and Jin has 80 points.

Episode 4 - Protect the Field of Flowers!

During an excursion, the boys of class 5-3 gets into a fight with the boys from the local. Meanwhile Kouji meets a girl called Kozue, who explains that the locals are angry that more and more trees are being cut for the expansion of the park for tourists. The next day, Class 5-3 hears that Onoboori mountain (the place they went yesterday) became treeless and a Jaku Beast is attacking. Still remembering the fight, Jin is reluctant to sortie. Kouji insist, saying it's their duty as the defenders of Earth and manage to convince everyone including Jin. With the help of the locals Raijin-Oh manage to defeat the Jaku Beast.

Episode 5 - Decision! Unrivaled Dragon Tail

Episode 6 - Survive the Traffic War!

Episode 7 - Taking Care of Drunkard

Episode 8 - Absolute Union of Friendship!

Episode 9 - Blowing Away Moldy Feelings

Episode 10 - The Town Where Gasoline Vanished

Episode 11 - Cookie's Nightmare

Episode 12 - The Pool is Too Hot

Episode 13 - Get Back the Baby!!

Episode 14 - Final Match! Baseball

Episode 15 - Fly at Mach 9!

Episode 16 - Crash Course in Returning the Shot!

Episode 17 - Teacher is a Jaaku Beast!?

Episode 18 - Presentation! Earth Defense Class' Secrets

Episode 19 - Seaside School is in Chaos!!

Episode 20 - Maria has Disappeared!

Episode 21 - The Enemy is Raijin-Oh!?

Episode 22 - Departure! The Invincible Warrior

Episode 23 - Come Forth! Absolutely Invincible Union!!

Episode 24 - Dog/Cat Panic Plan!

Episode 25 - Getting the Scoop!!

Episode 26 - Great African Battle!

Episode 27 - Defeat the Earthquake

Episode 28 - Garuma's Competition of Fear!!

Episode 29 - Appear! Super Jaaku Beast

Episode 30 - Jaaku beast is a Friend?

Episode 31 - Fierce Battle! Channel War

Episode 32 - Adventure in the Haunted House

Episode 33 - Terror! Dancing Jaaku Beast

Episode 34 - Skiing is Too Cold

Episode 35 - Vanished Commander

Episode 36 - Jaaku Beast is an Ally of Justice!?

Episode 37 - Graffiti Revolt

Episode 38 - Psychic Jin

Episode 39 - The Celebration is a Troubling Thing

Episode 40 - Belzeb's Great Approach

Episode 41 - Kidnapping of the Absolutely Invincible

Episode 42 - Protect the Secret of the School!

Episode 43 - Super Giant Reiko Appears!

Episode 44 - Decisive Micro-Battle!

Episode 45 - Broadcast! Earth Defense Class Facts!!

Episode 46 - Taida Becomes an Earthling

Episode 47 - Adult to Child Chaos!?

Episode 48 - Transformation! Black Taida

Episode 49 - Appear! Jaaku Empire

Episode 50 - Defeat Emperor Warza!

Episode 51 - Our Dreams are Absolutely Invincible!