The Tortoise and the Hare by Aesop. The Hare was once boasting of his speed before the other animals.
There once was a speedy hare who bragged about how fast he could run. Tired of hearing him boast, Slow and Steady, the tortoise, challenged him to a race. All the animals in the forest gathered to watch. Hare ran down the road. Once upon a time there was a hare who, boasting how he could run faster than anyone else, was forever teasing tortoise for its slowness. Then one day, the irate tortoise answered back: “Who do you think you are? The Hare and the Tortoise. One day a hare was making fun of a tortoise.
Full online text of The Tortoise and the Hare by Aesop. Other short stories by Aesop also available along with many others by classic and contemporary authors.