- Adored by the Network: PBS Kids gives this show a lot of good treatment. It gets consistent advertising, had its first 13 episodes released on the app, and gets 2 daily time slots on the main PBS network.
- Backed by the Pentagon: Some interviews mention that the estates of certain historical figures help out with the show.
- Children Voicing Children: This is the case with all three of the main child characters, and all of the historical figures when they were kids.
- Creator's Favorite: Brad Meltzer's favorite character is Brad, obviously.
- Early-Bird Release: "I Am Mary Shelley" aired as a sneak peek during PBS Kids Family Night on October 25, 2019. On November 11, 2019, all the episodes of the show dropped on the PBS Kids video app before they could air on television.
- Fake Brit: Afrodite Drossos as Mary Shelley and Florence Nightingale; Lucas Kalechstein as Charles Dickens.
- He Also Did:
- Out of Order: This is how the episodes air. Episode 9, "I Am George Washington/I Am Susan B. Anthony", was aired as the third episode when it's not.
- Recursive Adaptation: The show was based on a book series, then got its own books.
- Screwed by the Network: The January 2020 episode bomb didn't receive any advertisement, and like with many Nature Cat episodes in the latter half of season 2, PBS outright refused to release official descriptions for them. This is because PBS decided to focus on promoting The Rhythm and Roots of Arthur.
- The Wiki Rule: Xavier Riddle and the Secret Museum Wiki.
Trivia / Xavier Riddle and the Secret Museum