- D.W. has been blaming Arthur for her snowball's disappearance since D.W.'s Snow Mystery.
- The Brain made a couple inventions in Arthur's Tooth (episode) and Buster Baxter, Cat Saver (episode).
- Buster has a love for food throughout the series.
- George has been winning every contest since Buster's Growing Grudge.
- Baby Kate has been saying her first word since The Perfect Brother.
- Mr. Ratburn has no knowledge of technology since Best of the Nest.
- In the first few seasons of the show, there was a running gag with Mr. Haney. He'd randomly appear as a toy or a balloon, or something bad would happen to him, such as burgers hitting him on the face or being knocked off of his bed by the Tooth Fairy.
- Buster added tomatoes to desserts in The Half-Baked Sale and Buster's Sweet Success.
- Muffy's history reports usually contain references to modern things, such as when she said Ceaser Augustus was a salad and referred to Pilgrim clothes as "Pilgrim bling".
- In The Last of Mary Moo Cow, D.W. took away Arthur's bowl of popcorn a couple times and gave it to herself.
- In The Trouble with Trophies, Muffy tried to get Fern to win a trophy, but Binky ends up winning it instead.
- In The Rat Who Came to Dinner, D.W. was constantly butchering Mr. Ratburn's name (saying Mr. Ratburn's name incorrectly), and Mr. Ratburn ignores her.