Doug's building skills are put to the test when he and his classmates have a soda bottle rocket competition at school.
Doug and the Cadets take their first trip to outer space and learn about gravity.
Doug and the cadets embark on their first mission to Mars! There they must find a way to save the Martians' dwindling water supply from the Well of Being.
Dallas is being held prisoner on a comet! His fellow cadets must come together and find a way to rescue him.
Doug and the cadets finally get answers from Goro. But just as they start to take it all in, they're forced to compete in the Orion Pass Race.
Doug and the cadets must save the planet Dobo from another Class Exile - JoJo MeJo! But doing so is proving to be no small task.
Doug and the cadets join forces to try to sneak into the forbidden caboose.
Doug and the Cadets make a stop at the planet Blub - a world full of bubbles! There they must find a way to help the Bubblers reconnect with each other and enjoy the amazing world they have.
Doug and the cadets head to the Academy of Wanderers to retrieve important documents before the Exiles can get their hands on them.
Doug and the cadets follow a distress signal to the mysterious planet Brynthia where they face their greatest obstacle yet.
Doug and the cadets learn about their robot conductor's past.
The cadets are captured by Diva, an Exile obsessed with her own celebrity and one of Goro's former students.
After the power goes out in the Cosmic Cafe, the cadets are forced to stop at the planet Mudro for supplies. There's just one problem, Mudro has no food...
The cadets follow the ships from Mudro to a hidden mirror planet that reflects the stars around it. There they meet copies of themselves as they try to figure out who was stealing soil from the Mudro people.
Doug and the cadets finally meet the leader of the Exiles, a man who calls himself The Doctor.
Doug and the cadets learn about black holes as they're faced with a very difficult decision - destroy the Norb so that The Doctor can't get his hands on it, or keep it so that they can use the extra power against him? Find out in this week's episode!
The cadets receive a distress signal from the planet Grom. Every day, a deadly laser line beams down from the sky and creeps towards the Gromlers’ capital city. If the Gromlers don’t gather enough precious minerals by the deadline the laser will reach the city. Doug and the cadets must find a way to stop[...]
The Space Train and its cadets are captured by the Exiles and taken to witness the construction of The Doctor's latest project, The Academy of Exiles. The deadline for the cadets to enroll has arrived and The Doctor plans to do everything in his power to make sure they join him.
Doug and the cadets flee the Academy of Exiles only to come across a giant black sphere that is sucking all light and warmth from the neighboring worlds.
To avoid becoming slaves to The Doctor and his academy, the cadets and their parents confront the Exiles in a battle for their future.
The cadets salvage what they can from their battle with the Exiles and make plans for the future.