In the opening scene of the novel, Holden stands at the top of Thomsen Hill overlooking the Pencey football game against their rivals, Saxon Hall. Holden initially elaborates on how he was ostracized by the fencing team for losing their equipment on the subway before saying that he forgot to mention that he was kicked out of Pencey. Holden forgetting to mention the significant subject of his expulsion from Pencey characterizes him as a careless, absentminded individual. It also helps establish him as an unreliable narrator, who is willing to withhold significant information from the reader until he feels compelled to comment on it.

One could imply that Holden forgets to mention that he has been expelled because he does not think it is a big deal. Clearly, Holden is a careless individual, who has not taken his classes seriously and probably does not care about being expelled. Another possible explanation is that Holden is very nervous about being expelled and has repressed the thought of his expulsion. Thinking about confronting his parents about his expulsion could trigger Holden's anxiety, which is why he "forgets" to bring it up.

Holden has been kicked out of four schools before Pencey; he's never quite specific about why he was kicked out, though we know that he's flunked out of Pencey because he was failing four out of five classes. He's afraid to tell his parents for two reasons: one, he feels they would be upset, as any parent would be after a child getting kicked out of so many schools; and two, he's afraid to disappoint his parents again.