Although it's only a one way conversation, this marks the first time Chloe speaks to Jor-El.
In the Lois & Clark: The New Adventures of Superman first-season finale "The House of Luthor", Lex Luthor also trapped Superman in a kryptonite cage.
When Patricia gives Clark the journal, she mentions that it was transcribed by her father's assistant. Virgil Swann's assistant was Bridgette Crosby.
The book that Clark keeps the Key in is "The Adventures of Tom Sawyer" by Mark Twain. According to the series, Jonathan Kent's favorite book was "The Adventures of Huckleberry Finn".
Kara's yearbook dedication reads "This has been the best year ever! Thanks to all of my teachers and fellow students for their friendship and help. I will be modeling this summer."