Kim and Chris come to blows over his introduction of an APU (Advanced University Preparation) scheme for Ros, the school's brightest pupil, as the drama set in a Rochdale school continues.
Kim believes the scheme should be open to everyone, but Chris thinks it's cruel to build up pupils' hopes of getting into a top university if their grades aren't strong enough.
It's a battle of wills, won when Michaela stages a protest demanding to be allowed on the scheme and Rachel opens it up to everyone. However, Michaela soon learns she's not cut out for the rigours of academic life and Kim is left lecturing Chris on their need to address the aspirations of all Waterloo Road's pupils.
Elsewhere, year 10 pupil Aiden Keen has a bad attitude and a tendency to blame every slight or joke on the fact that he's very overweight. When Kim confiscates snacks from him during lessons, Aiden sneaks back into her empty office to retrieve them. Caught in the act, Aiden goes on the defensive and persuades his doting mother to lodge a formal complaint against Kim, suggesting she's bullying him because of his size. Rachel gets involved but it's not until Mrs Keen sees her son's attitude towards his peers and teachers, that she realises she's spoiling Aiden rotten and endangering his health by letting him eat junk food all day.
Rachel hires a new head chef to double up as Waterloo Road's healthy school coordinator which puts Ruby's nose out of joint. In addition the successful and extremely well-qualified candidate, Adam Fleet, turns out to be a welcome blast from Rachel's past....