Part of what makes "Teddy" so famous is its ending. There are actually a few different ways of interpreting that little girl's scream, though one in particular comes forward as the most popular, clear-cut, and convincing. Some will argue to the death that there's absolutely nothing ambiguous about this ending, while others insist that Salinger left it unclear intentionally. Let's take a look at the passage, and then a few different interpretations of it:
He [Nicholson] was little more than halfway down the staircase when he heard an all-piercing, sustained scream – clearly coming from a small, female child. It was highly acoustical, as though it were reverberating within four tiled walls. (5.33)
We're inclined – along with the majority of Salinger critics – to go along this route of interpretation. Teddy twice predicts his death in the course of narration. First, when he's writing in his journal: "It will either happen today or February 14, 1958 when I am sixteen. It is ridiculous to mention even" (4.20). The second is more explicit, and puts into context the "it" of this first prediction:
"I have a swimming lesson in about five minutes. I could go downstairs to the pool, and there might not be any water in it. This might be the day they change the water or something. What might happen, though, I might walk up to the edge of it, just to have a look at the bottom, for instance, and my sister might come up and sort of push me in. I could fracture my skull and die instantaneously." (5.9)
First and foremost, then, Teddy's death justifies him as a certifiable prophet/spiritual genius of sorts, which seems to validate everything he was saying to Nicholson. To those who interpreted Teddy as a poor, confused, but rather imaginative child (see Teddy's "Character Analysis"), sorry – not the case in this interpretation. Teddy not only accurately predicts his own death, but teaches Nicholson – and more importantly, the readers, how to react to it. As he says earlier:
"If Sven dreamed tonight that his dog died, he'd have a very, very bad night's sleep, because he's very fond of that dog. But when he woke up in the morning, everything would be all right. He'd know it was only a dream. […] The point is if his dog really died, it would be exactly the same thing. Only, he wouldn't know it. I mean he wouldn't wake up till he died himself." (5.11-5.15)
Teddy has already explained to Nicholson the uselessness of emotions – in particular any sort of grief over death. "They're still pretty afraid to die," he says of the professors in Boston. "It's so silly," he explains. "All you do is get the heck out of your body when you die. My gosh, everybody's done it thousands and thousands of times. Just because they don't remember it doesn't mean they haven't done it. It's so silly" (5.7).
This isn't just Teddy talking to Nicholson; it's Salinger talking to his readers, giving us hints as to how to deal with Teddy's death at the end of his story. Teddy is on to his next life; perhaps in a non-American body where he can better live spiritually. This is certainly nothing to grieve. As Teddy says to Nicholson: "What would be so tragic about it [my death], though? What's there to be afraid of, I mean? I'd just be doing what I was supposed to do, that's all, wouldn't I?" (5.9).
In Teddy's "Character Analysis," we discuss the possibility – as a few critics have suggested – that Teddy isn't actually a spiritual genius; he might just be a troubled child who has created a fantasy for himself in which he is some sort of prophetic guru. If you like that theory, you might be partial to this interpretation of the story's conclusion. Teddy, fed up with the world in which he lives, has chosen to kill himself. If this is the case, the ending is tragic, and if we buy into Teddy's claim that we should not grieve death, we are making the same mistake as the other characters in the story who failed to save him.
One of the issues readers take with the first interpretation is the seeming contrivance of the empty pool – why would Teddy have a swimming lesson scheduled on a day when the pool was emptied for cleaning? Why would the pool even be open on such a day? Of course, it's also possible that such details are simply meant to be ignored; one could find such contrivances in nearly every work of fiction. Another way to counter this theory is to take a look at the specific words used in the final line: It [the scream] was highly acoustical, as though it were reverberating within four tiled walls (5.33). This would seem to be Salinger's hint that the pool is – as Teddy predicted – empty.