- Seriously, of all the ways for Mr. D to get Percy's name wrong, his favorite is Peter Johnson? Especially given the reputation of his followers, back in the day
- At one point early in The Lightning Thief, Percy contemplates kicking his Jerkass stepfather Gabe in his "soft spot" and "making him sing soprano for a week".
- The series never outright calls any of the demigods illegitimate, though at one point Hera calls Percy "one of Poseidon's children," and Percy could tell that her tone was definitely implying something else, like "mistakes". Older readers might think of another term that applies to Percy.
- The fact that Chiron and Mr. D are running the camp together arguably counts, given that Dionysus was eromenos to Chiron in some stories, and apparently learned "the bacchic rites" from him.
- In The Lightning Thief, the "Honeymoon Special" waterbed in Crusty's Water Bed Palace has dynamic stabilizers to stop wave motion 'wink, wink, nudge, nudge'.
- Ganymede is mentioned in The Sea of Monsters (in both the book and movie), where he says he always buckles up in a recorded safety spiel in the Gray Sisters' Taxicab. His "special relationship" with Zeus isn't.
- In The Titan's Curse, Percy, Thalia, Grover and Zoe Nightshade arrive at the Hoover Dam, causing a hurricane of dam(n) jokes:Zoë Nightshade: "Let us find the dam snack bar."Grover Underwood [smiling]: "The dam snack bar?"Zoë Nightshade: "Yes. What is funny?"Grover Underwood [trying not to laugh] "Nothing, I could use some dam french fries."
- Also in The Titan's Curse, the quest group meets two male angel automatons. When Percy asks them if they've ever visited San Francisco, this conversation ensues:Hank: "We automatons gotta have some fun once in a while, right? Those mechanics took us over to the de Young Museum and introduced us to these marble lady statues, see. And"Chuck: "Hank! Theyre kids, man!"
- The Last Olympian:
- Percy mentions that a male and a female camper are not allowed to be alone in a cabin together. There's only one plausible reason for that.
- At the meeting with Hyperion, Thalia tells him "That's a load of Minotaur dung." Given that minotaurs are half bull, and "dung" is another word for "shit"
- There's an awful lot of dancing around the conditions for who can or can't be the Oracle. It's stated that May Castellan had major problems with it because she already had children. When Rachel becomes the new Oracle, they note that she won't be dating anyone anytime soon. If you're familiar with Greek mythology, you know that the Oracle had to be a virgin female.
- Percy Jackson's Greek Gods is pretty much the epitome of Getting Crap Past the Radar, as it reveals that the gods pretty much lacked morals. There's barely-disguised incest (usually with Percy snarking about it after), bestiality, adultery, suicide, murder, and sexual assault (even getting the word 'rape' past the radar).
- Of course this continues in Greek Heroes. Lord knows how any of these books got labelled for children.
Radar / Percy Jackson and the Olympians