The History Boys follows two teachers and a group of students at an all boys grammar school in England in the 1980s. The boys are all trying to get into Oxford and Cambridge. At the beginning of the play, we see Hector, a beloved teacher in his 60s, leading his General Studies class. He congratulates the boys on their recent exam results, and says that now that their exams are over, their real education can resume. Hector tells the boys that they shouldn't be so concerned with getting into the most prestigious universities, Oxford and Cambridge, because there’s a whole world outside of these places.
The school’s Headmaster wants the boys to attend prestigious universities in order to raise the profile of the school. He hires Irwin, a young Oxford graduate, to teach history and give the students extra “polish.” The boys meet Irwin during a funny scene in Hector’s class. The Headmaster walks in as they are improvising a skit, in French, about a brothel (Hector is using this method to teach the subjunctive verb tense). After this episode, Hector asks if anyone needs a ride on his motorcycle. We soon learn that Hector gropes the boys while they ride behind him on their way home from school. They discuss this matter-of-factly.
In Irwin’s classes, he encourages the boys to explore unconventional positions in their essays, even if they don’t fully believe them. He says that this will make them more competitive university applicants. Irwin begins to realize that the boys have a lot of literary knowledge from Hector’s classes, but that they don’t want to use it on an exam. He becomes more and more curious about what goes on in Hector’s classes, especially when he finds that Hector conducts class behind a locked door. We witness more General Studies sessions with Hector, in which he reminds the boys that literature will help soothe pain and heartache later in life.
Irwin tells Mrs. Lintott another history teacher, that Posner, one of the boys, came to see him recently. We have already learned that Posner has a crush on his fellow student Dakin, but that Dakin is sleeping with the Headmaster’s secretary, Fiona. Posner tells Irwin that he thinks he might be gay. In a narrative aside, Scripps (another student) says that Posner goes to Irwin because he has senses that they both have a crush on Dakin, and he “wanted company.”
Soon after this, Irwin asks Hector to encourage the boys to use their General Studies knowledge on the exam. Hector says that some knowledge is not meant to be “useful.” Irwin argues that education is for the present, not just for comfort in the boys’ old age.
Near the end of Act One, the Headmaster calls Hector to his office. He tells him that he has learned of Hector’s groping on the motorcycle. He asks Hector to retire at the end of the term. Hector quotes several lines of poetry, and begins to tell the Headmaster that “the transmission of knowledge is in itself an erotic act.” The Headmaster shuts him down, saying that his behavior “isn’t normal.” He says that Hector and Irwin will share their classes for the rest of the term.
In the last scene of the act, Posner and Hector discuss a poem about a young soldier who died in war. They both seem to relate to the poem, which has themes of being an outsider. Dakin enters wearing a motorcycle helmet, ready to go home with Hector, but Hector shoos him away, and rides off alone.
Act Two begins a few years in the future. Irwin is now a historian on TV. A man comes to visit him on set, and we later find out that it is Posner. He asks Irwin about his relationship with Dakin, and seems to be writing a piece of journalism on the subject. Irwin gets angry, and Posner leaves.
The narrative returns to years earlier, back in Hector’s classroom. The boys are joking around, and Hector becomes overwhelmed with discouragement. He puts his head on his desk, saying that he feels he has wasted his life. The boys are nonplussed, and Posner is the only one who moves to comfort Hector.
The Headmaster tells Mrs. Lintott about Hector’s groping, and says that he’s almost glad it happened. He’s been wanting to fire Hector anyway, because Hector’s results are so hard to quantify. He exits, and Mrs. Lintott tells Irwin that the Headmaster is a “twat.”
In their first shared lesson, Hector and Irwin discuss the Holocaust. Hector and Posner argue that one shouldn’t try to make a good point about the Holocaust on an exam, because this demeans the suffering of those involved. Dakin and Irwin argue that the Holocaust is an historical event, too, and can be discussed as such. A few scenes later, Mrs. Lintott, Hector, and Irwin giving the boys mock admissions interviews. Mrs. Lintott delivers a monologue about the way that women are marginalized in history while men get to make all the moves. Afterwards, Dakin asks Irwin about his time at Oxford. Their conversation becomes flirtatious.
We then hear from the boys, in narrative asides, about their exams and admissions visits. They have all received places at Oxford or Cambridge—even Rudge, who got in partly because his father was once a janitor at the university. Then Dakin confronts Irwin. While at Oxford, he learned that Irwin lied about being a student there. Irwin admits that this is true. Dakin seduces him, convincing him to come out for “a drink.” He teases Irwin for being rebellious in the classroom, but cautious in life.
Dakin tells Scripps that the Headmaster often makes passes at Fiona, and that he has used this information to get Hector a reprieve. He says that he’s going to ride home with Hector today, for old-times sake. When the Headmaster sees Dakin in a helmet, however, he forbids this. Instead he tells Hector to take Irwin.
We hear from Scripps, in a narrative aside, that the motorcycle crashed on the way home that day. No one knows exactly what happened, but Irwin was left crippled, and Hector is dead. The boys gather and share their memories of Hector. Then Mrs. Lintott tells us about their lives. Most of the boys end up successful in some profession, but Timms gets into drugs, and Posner ends up leading a lonely life, though he always remembers Hector’s teachings. The play ends when Hector says that the lesson he really wanted to teach the boys was this: “Pass the parcel. That’s sometimes all you can do. Take it, feel it, and pass it on.”