Season 3In Gangsta, Gangsta, he compliments Sean on his work on the car saying that he could work in his pit any day. Later in class, he is telling his students to pick up after themselves, and tells the students who have cleaned up "to get out of here".
In Our House, Sean reveals to Ellie that Mr. Ehl assigned a project that is worth 50% of his final grade, which is why he has spent so much time working on it. After Sean finds out that he has to move to Alberta because his brother, Tracker, was hired for a job there, he is visibly upset, and confides into Mr. Ehl about it. Mr. Ehl asks him about if he has checked into having student welfare, but Sean quickly scoffs at the notion. However, he tells Sean that if he keeps decent grades, then he would be the trustee, meaning he would legally be responsible for Sean. He tells Sean that he was the first person to graduate high school in his family, implying he wants Sean to have the same fate.
With no adult supervision at home, Sean lets loose and has fun, throwing parties and hanging out with friends in his apartment. Due to not focusing on school, he begins to fall asleep in class, as Mr. Ehl has to wake him up, and he begins to frequently arrive late to class. Mr. Ehl confronts him and reminds Sean he needs to focus on his other exams and the project due for his class.Later, Sean tells him that he had a party at his house and that the cops were called, saying that he would understand if Mr. Ehl didn't want to be his trustee anymore. Mr. Ehl tells me that he didn't want to be another person in Sean's life that let him down, but tells him that he won't sign the trustee papers until he can convince him that his partying days are over and that he is ready. Sean manages to convince him, and he signs the papers. Sean asks him if he can stick around and finish his project, which Mr. Ehl gives him a smile.