Take a story's temperature by studying its tone. Is it hopeful? Cynical? Snarky? Playful?
Playful, Tongue-in-Cheek, Sympathetic
Above all, the narrator's tone in the Alice books is playful – taking up jokes and kicking them around until they go somewhere absolutely crazy. We get the feeling that this narrator would do anything for a laugh, even if it means completely abandoning one plotline in order to follow up on a pun or a double meaning. Sometimes the tone is playful in an innocent way, such as when the narrator tells us about Alice's two kittens at the beginning of Through the Looking-Glass:
"One thing was certain, that the white kitten had had nothing to do with it: – it was the black kitten's fault entirely. For the white kitten had been having its face washed by the old cat for the last quarter of an hour (and bearing it pretty well, considering); so you see that it couldn't have had any hand in the mischief." (Looking-Glass 1.1)
In other places, the narrator is tongue-in-cheek, which is a fancy way of saying mocking or humorous in a lighthearted way. For example, Alice's astonishment at tumbling down the rabbit hole becomes a morbid joke between the narrator and the reader:
"Well!" thought Alice to herself, "after such a fall as this, I shall think nothing of tumbling down stairs! How brave they'll all think me at home! Why, I wouldn't say anything about it, even if I fell off the top of the house!" (Which was very likely true.) (Wonderland 1.7)
In other places, the narrator feels sympathy for Alice's bewilderment and difficulties. When Alice despairs of ever getting into the beautiful garden, the narrator pities her:
"Poor Alice! It was as much as she could do, lying down on one side, to look through into the garden with one eye; but to get through was more hopeless than ever: she sat down and began to cry again." (Wonderland 2.5)
Overall, the narrator is gentle, even when making fun of Alice or enjoying a private joke with the reader. We feel chummy with this narrator, who tells us secrets that Alice herself doesn't know, creating dramatic irony.