Young teachers join the faculty; students plan a walkout because of the administration's apparent lack of concern for student issues.

Senate's erratic behavior rattles Ronnie and prompts a telling showdown with Harper; pupil misconduct provokes a new teacher, whose youth belies grit.

Harper's meeting with a parent becomes heated; a new teacher stirs things up in the classroom; the teachers must evaluate one another.

A jailed Harper faces a manslaughter charge in the death of a student's father; a rebellious teen receives unsolicited help from Hanson, who uncovers the youth's dark secret.

Brooke feels guilty about leaving her father alone during the holidays; Lipschultz debates accepting his son's Christmas invitation; Marla and Kimberly are stranded at Doyle's during a snowstorm.

A teen's pregnancy sensitizes Guber; a gang slaying deeply affects Kimberly and her prize student; romantic liaisons have differing impacts on Ronnie and Hanson.

Harper has concerns about Brooke's infatuation with the star basketball player; Flynn is attracted to a student's mother; a boy enters an online auction to buy a night with a beautiful girl.

Kimberly is stalked by one of her students; Lipschultz celebrates Valentine's Day with Guber's mother.