The Time Machine
H. G. Wells, 1895.
Before you read: A dark future and danger underground. Better for older children.
A Victorian inventor tells his dinner guests that he has ridden a machine into the far future. He finds a soft, childish people on the surface and something hungry in the dark below. Wells is writing science fiction and a social argument at the same time: if the world splits into those who play and those who labor, both sides may become less human. The frame is a man talking in a parlor. The story he tells does not stay polite.
Public-domain text.