Story World is a location in Mario's Early Years! Fun with Letters. It is one of the additional two islands in the PC version of the game and is represented by a novel with a few pictures.
Story World's purpose is to teach the player how to understand words as they are used in basic context. It reads out a story selected by the player for them to hear, providing some text on the bottom along with a visual representation of the provided story as it is being read.
Story World is one of the only two worlds from Mario's Early Years! Fun with Letters that is not interactive at all, the other being Alphabet World. Its events start right after the player selects a story and then proceeds until the end. The player can leave during the storytelling if they desire by clicking on the green Warp Pipe at the bottom of the screen.
After playing in a mud pool, Icky Iggy sits on top of a napping Luigi. Bowser grabs Icky Iggy, and Luigi, apparently angry, gives chase. Bowser then tries to fit inside a log to no avail, getting stuck in the process. When Luigi sees this, he, Mario, and Toadstool are forced to free Bowser from the log. Bowser falls into the mud, and Mario and Luigi jump in after him, apparently having a lot of fun.
Toadstool owns a pig, which, because it is wet, she places onto a sun-warmed log, then gets a rag to dry off the pig. Mario and Luigi then grab the pig to ride it. Toadstool then comes back, angered to see that the pig is gone while instead a frog is sitting on the log. Luigi hides the pig underneath his hat, and he and Mario run from Toadstool. She eventually catches Mario, though the pig leaves Luigi's hat. The three sit on the log, and Toadstool gives Mario and Luigi each a hug, apparently having had a lot of fun.