While still in between jobs, Lily goes to work for Ted's architecture company but ultimately realizes she belongs back in the classroom, after Ted's boss, Hammond Druthers, is mean to Ted. She tries to teach him a lesson by using the same techniques she used to use on her kindergarten class. Ted is inspired by Lily and decides to take some serious chances at his firm. Also, Barney goes to great lengths to satisfy Marshall's sexy, older teacher, "The Cougar", who is recently divorced and has been taking it out on her class.