Awesome Music: The "Welcome Song" ("Gather 'round and sit right down, doesn't matter who you're next to...") and the class concert performance.
Also the show's music cues.
Ditto for the theme song.
Crowning Moment of Awesome: The climax of the first episode where Timothy tries protecting Yoko from an oncoming football only to get pushed by Claude. As a result, Yoko gives her honest opinion on Claude's arrogance while pulling Timothy off the ground.
Ear Worm: The shows theme song, the "Welcome Song", the "Snack Time" song, and the class concert performance
Memetic Mutation: Nora's scream in "Small Change" and Grace's Death Glare in "Full of Beans" were popular moments in Encore Enterprise's videos.
"I have a COTTAGE CHEESE sandwich!"
Lilly and Timothy's joke in "Don't Lose it Lilly".
Back in late 2007, a YouTube Poop surfaced that memed the scene from "The Mess Fairy" of Fritz and his mom in the kitchen.
Moe: A few female students such as Lilly, and especially Yoko and Juanita.
Charles is a male example, mainly due to his size and how innocent he can be most of the time. He also appears to be the youngest student.
Yoko has a cute laugh which can be heard when the students first enter Hilltop School in the first episode. Same goes for the ending where Timothy and Yoko are playing tag. Yoko also has a very friendly sounding voice complete with a cute Japanese accent.
On the topic of Yoko, her mother has the sweetest sounding voice and can be relaxing to hear along with Timothy's mother. Her accent along with Yoko sounds so soothing and very good. Yoko and her mother are both voiced by Japanese-Canadian voice actresses who speak very good English which explains why their accents sound so well and can be a little jarring to most viewers familiar with the Japanese Ranguage trope
Whenever Timothy's mother◊ speaks, it really shows how much of a good and caring mother she is with Timothy and how much she cares for other people such as The Franks. The fact that she's voiced by the same actress who voiced Little Bear's mother helps.
Anytime Timothy says "Wow" when he gets surprised or amazed.
Lilly giggles the most since she gets very excited very easily. Same goes for her speaking voice since it really shows how much fun she can have around even if she's forgetful or not.
Nightmare Fuel: The scene where Timothy gets himself trapped behind a door near the end of "Shy Charles"
Superlative Dubbing: While the voice actors for the child characters were good in English, the French version of the series is also very good; special mention goes to the French voices of Timothy and especially Yoko who both have cute sounding voices and show more energy with the characters' feelings.
Sweet Dreams Fuel: A sweet and innocent little show about going to school and learning life lessons in friendship and kindness.
Toy Ship: Timothy x Yoko and Charles x Lily are practically canon. Claude x Grace could also be seen as this.
Viewer Species Confusion: Fritz and his mother. Are they skunks? badgers? Nobody seems to be sure. Even looking at official reviews for the original Rosemary Wells book that he appears in, Fritz and the Mess Fairy doesn't shed any light on the subject. Publisher's Weekly calls him a "skunk," Kirkus Reviews describes him as a "badger." Presumably, this applies to Miss Appleberry (the occasionally-seen student teacher) by extension, as she appears to be the exact same species as Fritz.
The Woobie: The show loves doing this to Yoko. She has been teased about what she brings for lunch in "Yoko" (in the show and in her 1998 book debut), had the Franks break her taketombo in "The Taketombo" (they later fix it), and for her Japanese family figures being stolen in "Lost and Found" (they're later returned, though it's not revealed who did it).
Any time Timothy gets very sad. He really becomes this in "Timothy Goes to School" and "Fritz on the Move."
Grace whenever she gets very upset when something bad or something very unexpected happens to her. She becomes this in "The Talent Show" when she sprains her ankle and can't be in the show.
Juanita is this in the final two episodes. She constantly doesn't want her mother to leave during her first day in school. She is also very lonely and shy while trying to make a new friend.
Lilly in "Lifesaver Lilly" where she hopes to take care of the class pet but never got picked due to her being very forgetful. While Lilly's forgetfulness is usually for minor things such as forgetting where her pencil is, this episode takes this issue very seriously and at one point, Lilly thinks that she lost her fishbowl which had her pet goldfish named Treasure and starts crying in fear thinking she lost her pet.