When the students are discussing Annalise Keating's firing, Asher says they need to storm the President's office and do an "O'Captain, My Captain." This is a clear nod to the movie Dead Poets Society, in which Robin Williams' character, Professor Keating" is fired. Students recite those lines to show their respect at the end of the film.
The scene where Keating shows up to her AA meeting is filmed in the exact location Kan (Laurel's Ex) worked at in the first season.
Beginning in S1E2 the title of each episode is spoken by a character in the episode. Wes is the one who says 'It's about Frank' when he and Laurel visit Annalise.