The central conflict of the story is that Margot does not fit in with the other children.
The basic situation is that it has been raining on Venus for seven years. The children, who are nine years old, do not remember ever seeing the sun. The sun is scheduled to come out, so the kids are very excited. Margot is excited too, but she is a child who just doesn’t fit in.
Margot is from Earth, and the other children are from Venus. In addition to that, Margot is delicate and sensitive and just doesn’t associate with the other kids.
They turned on themselves, like a feverish wheel, all tumbling spokes. Margot stood alone. She was a very frail girl who looked as if she had been lost in the rain for years and the rain had washed out the blue from her eyes and the red from her mouth and the yellow from her hair.
The other kids tease Margot and don’t understand her. They are envious of her, and like many kids they turn that envy to cruelty. When the class is preparing for the sun to come out, the children tease Margot for the poem she wrote. She remembers the sun, and that really eats at them.
When the teacher leaves the room just as the sun is about to come out, the conflict comes to a head.
"Get away !" The boy gave her another push. "What’re you waiting for?"
Then, for the first time, she turned and looked at him. And what she was waiting for was in her eyes.
The boy tells Margot it was all a joke, and suggests they lock her in the closet. He is using her desperation and expectation against her, even though all of the children want the same thing. They are all ramped up, and need a target for their energy and aggression. Margot is an easy target.