If there was a new student in Wellington High School, I would make sure to show and tell them the most important things about living in this strange little town, and going to our strange little school.
First off, I would tell them that they need to show their rocket*pride! It would be much easier to make friends in this crazy place if you're not afraid to cheer on your new favorite football/basketball/baseball teams.
I'd also make sure to tell them about all of the crazy and interesting teachers in our high school. For example, Mrs. Cudd's stories will teach you more about foreign countries than any book ever could do. Mr. Hays is possibly the best math teacher anyone will ever have, and one should always ask him about Gog, and Gug, and the land of Ug [a.k.a. the story of the beginning of the Pythagorean Theorom]. I'd also be sure to tell them the locations of the best places to when not in class, and who to ask when they are in trouble.