When Franklin tries to live up to the nickname he chooses for himself, he learns you can't ignore who you really are.
When Franklin realizes that his favorite athletes all have cool nicknames, he decides that he wants one, too. So he asks everyone to call him "Flash." His friends point out that nicknames are never self-chosen; you get one based on something you do. They decide that Franklin should be called "Pokey," since he moves slowly. This sets off a contest in which Franklin tries to disprove his friends -- but his true nature wins out. Franklin decides to wait for a nickname until he's earned one that really suits him.