When Sue makes her announcement over the P.A., Becky does an intro and outro on a small xylophone. She is stopped by Sue when she hits too many notes; this is reminiscent of the principal's secretary Blanche in Grease (1978), who does the xylophone intros and outros for P.A. announcements, and also gets carried away.
When Rachel and Kurt are waiting for Blaine so Rachel can kiss him, she says, "I may get a new boyfriend who can keep up with me vocally and in the future give me vaguely Eurasian-looking children". Darren Criss, who plays Blaine, is half-Filipino.