Principal Owens is tired of hearing from angry parents and wants Mr. Ross to stop The Wave. However, Mr. Ross asks for just one more day to teach the students “a lesson they will never forget” (123). Principal Owens agrees, but threatens to fire Mr. Ross if The Wave gets any further out of hand.
In class, Mr. Ross announces that The Wave is part of a national movement to turn the country around. He tells the students that through the values of The Wave, they will be able to solve problems like inflation and unemployment. He adds that this afternoon, there will be a Wave rally where the students will hear from the movement’s national leader. The students in the class are enthusiastic, except for Laurie and David. They think that Mr. Ross has gone back on his promise to end The Wave. Mr. Ross puts Robert in charge of the class and escorts Laurie and David to the principal’s office. On the way there, he explains that this is all part of his plan to end The Wave.
Laurie and David don’t believe Mr. Ross. When they get to Principal Owens’s office, they beg him to stop The Wave, but he tells them not to worry about it and sends them back to class. Frustrated, Laurie and David skip school for the rest of the day. David confides in Laurie that he is embarrassed that he got so taken in by The Wave. She reminds him that there are good things about The Wave, too, and it’s not his fault he got caught up in it like everyone else.
Laurie and David talk more about how scary The Wave is. They remember their discussion after seeing the concentration camp movie. David had said that such atrocities could never happen again, but now Laurie isn’t so sure. They decide to sneak into the Wave rally to see what Mr. Ross has planned.
Meanwhile, Mr. Ross heads to the gym for the rally. Students are outside, checking membership cards to make sure that only Wave members are allowed in. Christy drops by to wish him luck. Inside the gym, the students spontaneously begin to chant The Wave’s mottoes as Alex and Carl set up the film on the projector. Meanwhile, David and Laurie try to enter the gym but the doors are locked. They are able to slip in during the confusion that ensues after a student gets angry that the televised address hasn’t come on yet.
Eventually, Mr. Ross begins his speech. On the televisions, the concentration camp film begins to play. “There is your leader!” (134) he says, pointing to an image of Adolf Hitler. He lectures the students, explaining that they would have been “good Nazis” (135) and they must never prioritize the will of the group over their own freedom. The students are stunned and ashamed of themselves, and they slink guiltily out of the gym.
Laurie and David approach Mr. Ross after the rally. They thank him for the lesson and apologize for not trusting him. He thanks them and apologizes for not telling them his plan. He explains that while The Wave was successful in teaching the students about fascism, he does not think he will repeat the experiment next year. Laurie and David leave, and Mr. Ross is left alone with his thoughts.
Or so he thinks. He turns around and sees that one person is left in the room. Robert is quietly sobbing to himself. Mr. Ross feels guilty about how the experiment has affected his worst student. He tells him he looks good in a suit and invites him to dinner. “There are some things I think we should talk about” (138), he says to Robert.
In the final chapters of The Wave, Strasser both embraces and rejects an easy resolution. All of the loose ends seem to be tied up––Mr. Ross solves his marital problems with Christy and manages to keep his job; Laurie and David get back together; Amy and the other students who embraced The Wave get their comeuppance.
Mr. Ross’s speech also neatly summarizes the morals of the story: individual freedom must always come before group unity, and while people prefer to have leaders, they must think critically about whether their leaders deserve their allegiance. As Mr. Ross reflects on The Wave, Strasser shows that the teacher has learned some lessons too. He did not control The Wave carefully enough, and underestimated the powerful human compulsion to submit to a leader.
However, The Wave also resists simple resolutions. Amy and Brian are both awkward when they see Laurie and David after the rally; although they have undoubtedly learned their lesson, it becomes clear that The Wave will have lasting affects on the students’ friendships. Robert is also hurt by The Wave, and Strasser does not offer any easy answers about how students like Robert can find a better way to integrate themselves into society.
Although Laurie and David appeared to reconcile with Mr. Ross at the end of the previous section, it becomes clear in Chapter 16 that they still do not entirely trust their teacher. Strasser portrays their skepticism positively; at the end of the book, Mr. Ross says, “It’s good that you didn’t [trust me] ... You showed good judgment” (137).
When his characters must choose between individual, critical thought and obedience to a leader, Strasser always seems to endorse critical thought––even when it results in his characters getting sent to the principal’s office. In addition to the lessons Mr. Ross describes at the rally, the overarching message of the novel is its endorsement of constant critical thinking––even at the cost of one’s social or academic status.