A monologue is a speech performed by one actor or reader that requires the attention of the audience be almost entirely on him. If you need to perform a monologue for a speech or drama class, you can use one that has already been written or come up with a topic that affects you personally and expound on it for your class.
Read Shakespeare's works for dozens of fabulous monologues you can perform for your class. Recite Hamlet's "To Be or Not to Be" soliloquy, or Jaques' "All the World is a Stage" monologue from "As You Like It." Try a comic monologue from "A Midsummer Night's Dream," like Puck's that begins with "My mistress with a monster is in love," or Helena's that begins with "How happy..."or Monologuearchives.com.
Read a first-person poem as a monologue, like Edgar Allan Poe's lengthy "The Raven," or look through Homer's "Odyssey" for one of Odysseus's monologues. Try Robert Browning's "My Last Duchess" or poems by Ezra Pound, Sylvia Plath or T. S. Eliot.
Research a topic you feel strongly about and argue your point of view. If you believe global warming is affecting our society, discuss that. If you think J. D. Salinger is an overrated writer, try to convince your audience in a heartfelt speech. Any topic that you are interested in will make a good monologue topic if you bring your passion to the speech.
Tell a funny story or write a series of jokes to make up your monologue. Comedy can be very difficult to pull off, so you'll want to try out your material on friends before you bring it to class. If your comedy is successful, however, you'll likely be the most popular person in class on the day you deliver it.