To test his students and to see if they are paying attention, Spock puts false points in his lectures. Many wouldn't dare point this out our argue against anything he says except Uhura. He finds her challenging him "stimulating" and she's about to find out just how much. I'm going for the whole bickering foreplay angle.

Spock: "Your argument is flawed."
Uhura: "No, your argument is flawed!" She said standing in class. Other students aka the peanut gallery ruffled in their seats. "Oh here we go." "Tell me about it." "Nerds." "Might as well call a free period because they are going to be at it for a while." "I never know what they are talking about." "It's like they get off on debating all the time."