It would better improve the paragraph because it has nothin to do with the rest of the paragraph. The paragraph seems to be about team sports and promoting it, while sentence 3 is about individual sports are better then team sports. So removing sentence three would better promote CO-ED team sports.
What do you need help with that's a good start so far
This is true. Narrative stories are usually fictional, but some authors write narrative stories that are kind of similar to memoirs in the sense that they document a true experience from the author's life.