- The names Calvin and Hobbes are taken from a 16th-century theologian (John Calvin) and a 17th-century philosopher (Thomas Hobbes).
- In the tenth anniversary book, Watterson notes that Miss Wormwood is named after the apprentice devil in The Screwtape Letters. He also comments on naming his leads after theologian John Calvin and philosopher Thomas Hobbes.
- In an early Sunday strip when Calvin and his parents went to an art museum, in one panel, his parents are admiring a Krazy Kat landscape. If they're not in museums, they should be.
- Hobbes once does Calvin's hair for school picture day. Calvin keeps asking him how it looks and Hobbes finally tells him that he looks like Astro Boy. Upon hearing that, Calvin exclaims that he can't wait to get his picture taken.
- One Spaceman Spiff strip has him finding a planet with a city and civilization that are the size of ants, likely an ode to the episode "The Little People" from The Twilight Zone (1959).
- In an arc in which Calvin gets turned into an owl with his transmogrifier gun, when he realizes that owls don't have to go to school, he starts singing the "Zip-a-dee-doo-dah" song from Song of the South.
- Another Disney tribute: "When you wish upon a star, your dreams come true... I WISH I HAD A COOL MILLION DOLLARS, RIGHT NOW!... If Jiminy Cricket was here, I'd skoosh him."
- One comic had Calvin wearing a cape and shouting "Up, up, and away!" in an attempt to fly. After he crashes he shouts "Ack! Kryptonite!"
- There was also a Sunday strip where Stupendous Man reversed time by spinning the earth backwards.
- When Calvin and Hobbes imagine superheroes going after mundane supervillains, they imagine one attending council meetings and sending letters to the editor. Hobbes then exclaims "Quick! To the Bat-Fax!"
- In one strip Calvin claimed he was attacked by space aliens that looked like "baked potatoes with ray guns."
- After one of Calvin's antics, Rosalyn tells him ''BEDTIME FOR BONZO!"
- When asked by Miss Wormwood the location of the Byzantine empire, Calvin replies "I'll take Outer Planets for $100."
- Watterson is apparently a big fan of "Nude Descending a Staircase", since Calvin tries to replicate it twice in two different mediums (snow sculpture and live-action.)
- On one occasion, Calvin calls Rosalyn "The Babysitter from the Black Lagoon."
- Elmer Fudd and Bugs Bunny have been featured among the TV shows Calvin watches, judging by the dialogue coming from the TV.
- Calvin describes his onion costume as Jabba the Hutt meets Rudolph the Red-Nosed Reindeer.
- Calvin's dad spends one strip criticizing a Merchandise-Driven cartoon, calling it "boring" and "preachy" and saying the animation was very lazy; in the final panel, Calvin rolls his eyes and says: "Meet my dad, the Gene Siskel of Saturday morning cartoons."
- When Hobbes gives Calvin a bad haircut, Calvin frantically wonders how he can hide it from his mother. Hobbes wraps a towel around his head, calling it the "Lawrence of Arabia look."
- William Shakespeare is referenced with two comics. In one, Calvin fantasizes his food coming to life and giving Hamlet's "To be or not to be" speech in its entirety. Another has him imagine him and his mom speaking Shakespearean English to each other while he watches a TV version of a play on TV.
- Calvin tells his mom he wants to grow a long beard "like the guys in ZZ Top".
Shout Out / Calvin and Hobbes