Character mistake: In the scene where Kris's knowledge is being tested, he incorrectly gives the vice president of President John Quincy Adams. Kris states John Quincy Adams' vice president was Daniel D. Thompkins. That's wrong. John Quincy Adams' vice president was John C. Calhoun. Daniel D. Thompkins was the vice president under President James Monroe.
Continuity mistake: When Dr. Sawyer is giving Kris the exam, during the part where Kris is doing the physical coordination test, we see Kris from Sawyer's point of view, and Sawyer is drumming his fingers. When the shot switches to Kris's, he is fingering his eyebrow. When it switches back, fingers drumming. Finally, when it switches back again, his hands are neatly folded in front of him.