This play is a very famous comedy written as a parody about the English aristocracy in the eighteenth century. The play has two main plot threads both of which come together in a hilarious ending.
Both plot threads involve Sir Oliver Surface's two nephews in some way. The first thread is about Sir Oliver Surface trying to determine which nephew most deserves recognition. The second main thread involves Lady Sneerwell's plan to trap both nephews as well as Lady Teazle.
The two separate stories of the play come together in a grand way during the final act. Both Sir Oliver and Sir Peter find out about Joseph's true character while Charles receives both Maria's inheritance as well as his uncle's inheritance all because of a promise to do better. Snake is paid double in order to expose the truth about Lady Sneerwell (whose tricks are found out as a result), and at the same time, Lady Teazle returns her diploma back into the School. Ironically, Lady Sneerwell continues on as the president of the aptly named "School for Scandal."
In conclusion, it's important to note the significance of names in this play. One can't get far without realizing the comic nature of last names based on the words surface, sneer, snake, and tease. Everything humorous and comic lends itself to the play's hilarious conclusion.