- Actor Allusion:
- Rin usually shows up with her ass facing the camera, in the same vein as Crayon Shin-chan.
- Nozomu was once depicted wearing a Celestial Being space suit, and behind him is what looks like Tieria Erde — both are voiced by the same guy.
- One chalkboard gag also features Nozomu drawn in the style of On the Next Bakemonogatari, and one scene where he brought a flight simulator in class even depicts him in a Celestial being spacesuit, with a Tieria lookalike behind him. Another instance might be the naming of the series.
- A quick shot early in the anime shows Nozomu reading Honey and Clover, where he voiced one of the protagonists.
- Sensei's old friend happens to like girls with pony tails. The old friend is voiced by Kyon, who also likes pony tails.
- Abiru once chased a giraffe with a scooter. Her voice actress is a Real Life motorcycle enthusiast.
- In Episode 5 of the first season, Kafuka is shown on an "Unlucky Channel" set — Her voice actress also voiced Akira Kogami for the Drama CDs and DS game of Lucky Star. And in another, she holds a starfish◊, as an obvious nod to Fuuko Ibuki.
- Colbert Bump: The series gained some new fans because a certain Katawa Shoujo parody game used Kuuso Rumba as its main theme.
- Development Hell: The English release of the anime was announced by Media Blasters back around 2008, but they sat on the license too long and nothing came out of it. Finally subverted nearly 11 years later when Nozomi Entertainment announced it would finally be releasing it on DVD and Blu-ray, alongside a brand new English dub, in 2020.
- No Export for You: The English release of the manga stops at volume 14. The other volumes are out of print, too.
- Relationship Voice Actor:
- Nami, Maria and Abiru are Sae, the Landlady and Hiro.
- Nami, Maria, Kafuka and Nozomu are Akira Miyata, Akane Serizawa, Ichijou and Tsurugi Inugami.
- Matoi and Maria are Dejiko and Puchiko and Jun and Shinku, with Ai being Barasuishou in the latter.
- Nami, Maria and Ai are Milfeulle, Mint and Chitose, and Rachel, Claire and Jessica.
- Matoi, Kaere/Kaede, Chiri, Nami, Ai, and Maria would later be Kanako, Mariya, Matsurika, Sachi, Yuzuru and the Dorm Leader.
- Schedule Slip: It didn't actually happen per se, but various comments within the show itself and Shaft's well publicized problems with meeting deadlines over the last year or so indicate that they came very close to this with Zan, and may explain the lower quality of animation compared to the first two seasons.
- What Could Have Been: An early pitch for the manga was that it was a Black Comedy but otherwise lighthearted romance between two very different people: Nami was going to be a stuck-up delinquent who never went to school, while a male Komori was going to be a nerdy, academics Hikikomori who never left school. However, it ended up as a...black comedy, but otherwise lighthearted manga about the romance of two completely different people...huh.
Trivia / Sayonara, Zetsubou-Sensei