It's the air-raid siren, screaming its horrible scream int eh playground, high over our heads on a thousand-foot telephone pole - and we are outside. Outside. o desk, o turtle, no cover."
-- Franny (chapter 1 paragraph 29)

Importance: Franny is describing the situation when they are on the playground, rather than in their classroom, when the siren goes off. They are supposed to "duck and cover" as they have been taught through the actions of a public awareness campaign featuring Bert the Turtle, but they have always done the drill using their desks for cover. This time, they do not have that. The fact that Franny identifies the telephone pole as 1,000 feet tall is an indication of her perspective. She is a child, but the pole seems incredibly tall because it holds the siren.

I can picture the dinners in their houses tonight, the talk around the table, all about the Chapmans, who moved in on...
-- Franny (chapter 4 paragraph 9)