Air date: April 16, 2019
- Written by: Joe Purdy
Carrot is about to turn 250 Bortronian years old, and the kids have set up a backyard circus to help him celebrate. They all notice that Earth's gravity makes it hard to perform their circus stunts, so they take the whole circus to the Moon, where its 1/6th gravity makes all their stunts much easier!
- Birthday Episode: In this episode, Carrot has his birthday.
- Cannot Keep a Secret: Jet was unable to keep the secret about the surprise party, and neither was Carrot. Celery says that it's a shared trait.
- Circus Episode: The episode focuses on the kids setting up a circus for Carrot's birthday. They can't do their stunts on Earth, so they take it to the moon instead.
- Gratuitous Disco Sequence: Part of Carrot's famous flip is to do a disco dance.
- The Last of These Is Not Like the Others: When the gang is trying to think of places to take the circus to, Sean suggests Mercury, Jet suggests the comet Churymov-Gerasimenko, and Mindy suggests Edmonton, Alberta. Sean and Jet's suggestions are both from outer space, while Mindy's suggestion is the capital of a Canadian province.
- Like Parent, Like Child: Celery says this trope's name out loud when comparing Carrot and Jet's shared tendencies to not keep secrets. She also offhandedly mentions that they both like prune juice with lemons.
- Nice Hat: Everyone gets a nice hat to wear when they do their circus tricks on the moon.
- Nice Job Breaking It, Hero!: When Jet blabs out loud that they're planning a surprise party for Carrot, unaware that Carrot is listening. Carrot also gets a moment of this when he says out loud that they're planning a surprise party for him.
- Overly Long Name: When the gang plans to take the circus to the moon, they come up with a bunch of overly long codenames for the mission. Of freaking course, it's Mindy who comes up with the simple one that ends up getting praised by the characters and ultimately used: Moon Circus.
- Secret Secret-Keeper: Carrot overhears from the kitchen that Jet is planning a surprise party for him. Carrot then has to keep the secret that he knows about the surprise party, but ends up telling Jet anyway.
- Shout-Out: Carrot's disco dance is a reference to the one John Travolta's character did in Saturday Night Fever.
- "Staying Alive" Dance Pose: Carrot assumes this pose when he does his famous flip.
- Stock Footage: Footage from "What Goes Up..." is reused during the "What Goes Up (Must Come Down)" song, but there is some new animation and new voice-clips, except all the kids sound terribly off-key this time around, a far step down from the original.
- Surprise Party: The kids plan one for Carrot, though it's not much of a surprise later on.
- Title Drop: Mindy name-drops the episode title when she comes up with a simple codename.
Every Day Is Earth Day
- Written by: Michelle Lamoreaux
It's Earth Day, and the kids are preparing posters for the big community celebration at the DSA. They decide to research their posters by traveling all around the Earth in Jet's family saucer and observing all the things that make Earth so special.
- Absentee Actor:
- Sadly, Face 9000 as per usual.
- All of the Earthies appear in this episode, except for Lillian.
- Adorkable: Mitchell is lovably awkward and shy when reciting his poem about Earth.
- All Deserts Have Cacti: Sean points out that deserts have cacti in them.
- Balloonacy: Sunspot is able to puff up like a balloon, and Jet flies away while holding on to him.
- Breaking the Fourth Wall: After it is mentioned that Earth is the only planet with life, Jet looks at the audience and says "That we know of!" and then winks, since he's an alien from another planet.
- The Cameo: Dr. Rafferty, Dr. Bergs, and Dr. Skelley make cameos.
- Crowd Song: The song featured in the episode is first sung by Jet, and then by everyone.
- Cutaway Gag: When Jet mentions how he and his family always mix up certain words, it cuts to Carrot and Celery hammering toasts on the wall, instead of posters.
- Everything's Better with Sparkles: Mindy sure thinks so, but Sean isn't sure how that will improve her poster.
- Holiday Episode: This episode focuses on Earth Day.
- I've Heard of That What Is It?: Jet says that he loves Earth Day, but then asks what it is.
- Malaproper: Carrot mistakes "toaster" for "poster" and presents a toaster at the DSA celebration, much to Mr. Peterson's annoyance.
- Mondegreen: Jet mishears "habitable" as "habit-a-bubble".
- Straight Man: Mr. Peterson makes a comeback as this trope in this episode, being the serious one compared to Carrot's silly antics.
- Wink "Ding!": When Jet winks, a "ding" sound can be heard.
- The World Is Just Awesome: The main theme of the episode is just how amazing and unique Planet Earth really is.