When the gang find King Bob in the kindergarten area, the "B" on his crown is missing.
When King Bob tells the kids that he wasn't first born in his family, the stripe on Gordy's shirt is missing, Ashley Q.'s drawn over Ashley A., Ashley T.'s face is missing, one background kid is drawn over the monkey bars, and one more background kid is missing an arm.
This is the second episode where T.J. gets a black eye, the first being "The Shiner." This is, however, the only time he received one on purpose.
It's revealed in this episode that King Bob has an older sister named Shiela, Lawson has an unnamed older sister, and Spinelli has another older brother named Vito, who gave her her trademark boots.