"The Lottery" by Shirley Jackson is a story which contains many examples of irony.
The first, of course, is that the title and opening paragraphs all indicate that the lottery is something positive and beneficial when, in fact, it is anything but that. The day is normal and beautiful, and the lottery is compared to a square dance and an innocuous Halloween party. In actuality, the lottery is a dance with luck that will end in a stoning.
Another irony is that everyone in town seems to care about one another, wanting to make sure no one misses out on the festive occasion; what they really want, we learn, is to be sure everyone has the same chance of losing as they do.
It is also ironic that Tessie Hutchinson actually encourages her husband to go pick his piece of paper:
"Get up there, Bill," Mrs. Hutchinson said.
His selection, which she is so eager for him to make, leads directly to his wife's death, and that is ironic.
At the beginning of the story, Mrs. Delacroix is a sweet and loving friend to Tessie; however, things change quickly and, by the end of the story, the image we have of her changes dramatically.
Mrs. Delacroix selected a stone so large she had to pick it up with both hands and turned to Mrs. Dunbar. "Come on," she said. "Hurry up."
It is ironic that the loving mother Tessie is in the beginning of the story becomes a mother ready to sacrifice even her children to save herself.
The final irony is Tessie's final protestation:
"It isn't fair, it isn't right," Mrs. Hutchinson screamed, and then they were upon her.
This is ironic, of course, because if anyone else but her had been the lottery loser, she would have thought the lottery was perfectly fair and been quick to pick up her share of stones.