Rudyard Kipling's short story "Rikki-Tikki-Tavi" describes a mongoose's coming of age. The protagonist, Rikki-Tikki-Tavi, is initially inexperienced, as shown by his first battle against the cobra in which "if he had been an old mongoose he would have known that then was the time to break her back with one bite; but he was afraid of the terrible lashing return-stroke of the cobra" (Kipling 30). Over the course of the story, Rikki-Tikki-Tavi becomes wiser until the resolution, when he defeats the cobras. The protagonist displays his maturity by avoiding excessive pride (Kipling 111). Rikki-Tikki-Tavi will most likely continue to win fights against cobras with experience because he developed maturity by the end of the story.
(My page numbers might be different from yours, which would show your teacher that you got your answer from someone else. Double-check the page numbers in your book.)