David's time at Doctor Strong's passes by almost without him noticing it, although certain incidents and impressions stand out. He is in awe of the head boy, for instance, and cannot imagine ever becoming the head boy himself (though Agnes says he might). He is also infatuated with Miss Shepherd—a girl at a nearby boarding school who attends the same church services as David. He eventually meets her at a dancing school, and the two carry on a youthful romance, exchanging presents and, at one point, a kiss. Eventually, however, David learns that Miss Shepherd prefers another boy over him, and the two drift apart.
Although he can't quite picture himself as head boy, David's admiration of the current head boy reflects his desire for self-improvement and his ability to set goals for himself. The fact that Agnes encourages these hopes is an indication of the role she plays in David's life, gently pushing him to better himself and grow.
Now slightly older, David enters a phase where he finds the boarding school girls irritating. He is doing quite well at school, but is troubled by the appearance of a bully: a "young butcher" who dislikes the students at Doctor Strong's and beats several of them up. David decides to fight the butcher and is badly defeated, but takes comfort in Agnes's support.
Although David doesn't say so explicitly, the rivalry between the butcher and Doctor Strong's students likely grows out of class tension; the butcher seems to feel personally insulted by the middle-class students, presumably because he senses that they look down on him. Agnes, meanwhile, continues to act as a model Victorian woman, offering comfort and support to David when the outside world overwhelms him.
Time passes, and the former head boy returns to visit Doctor Strong's. He is studying to be a lawyer, but David no longer finds him as impressive as he once did. In fact, David himself becomes head boy soon after this, and begins to take a "condescending interest" in the younger boys, who remind him of his former self.
As David grows older, his perceptions of the world and his place in it shift. Because David now realizes that he is capable of similar success, he doesn’t find the former head boy so intimidating. That said, his fondness for the younger students, however patronizing it is, also speaks to some nostalgia for his younger self.
Agnes has also grown up, though she remains David's "counscllor and friend." David, however, is preoccupied with a new love interest: the eldest Miss Larkins, who is roughly 30 and implied to be a bit of a flirt (David is particularly distressed by the fact that Miss Larkins knows several officers). David's entire life revolves around Miss Larkins: he dresses with her in mind, finds himself fascinated by anything remotely connected to her, and fantasizes about saving her from a house fire.
David's infatuation with Miss Larkins is a sign of how much more growing up he still has to do. David pokes fun at himself as he describes his past feelings, implying that they were both excessively passionate and lacking in depth. What's more, he's so carried away with romantic fantasies that he fails to recognize the fact that Agnes is essentially already functioning as his wife by providing him with unwavering support and companionship.
Eventually, David is invited to a party Miss Larkins will be attending; he prepares for this event obsessively in the hopes of declaring his love for her. David does in fact manage to dance with Miss Larkins, and as they sit together afterwards, he asks for one of the flowers she's wearing in her hair. He spends the rest of the night in a state of "unspeakable bliss." Afterwards, however, he does not see Miss Larkins for several days. Finally, Agnes informs David one evening that Miss Larkins is marrying a hop-grower the following day, which sends David into a fit of depression. Within a few weeks, however, the prospect of once again fighting the butcher brings him to his senses.
David's quick recovery when he learns Miss Larkins has married is another indication that his feelings for her weren't really mature love. One of the main lessons David learns over the course of the novel is that romantic love alone isn't enough to sustain a marriage, and that factors like compatibility also need to enter into the decision.