If you're in a 19th-century or Victorian literature class, write about how the text comments on the larger society; Victorian writers liked to incorporate criticisms of the legal system, especially prison life, and the plight of illegitimate children into their works. Consider the author and his background. For example, Charles Dickens wrote much about England's penal system, and much of it is informed by his experiences working in a factory while his father was in a debtor's prison.
Choosing an original and interesting topic for a political science class can be quite difficult, given the large number of college students who take such classes. Depending on your class, you can write about different things. For example, if you have an open-topic format, write about the rise and development of a populist group, like the Greenback Party in the 1870s and 1880s or about how the United Nation's Security Council would be affected by the granting of a veto vote to a sixth nation like Japan.
Students across the country take U.S. history classes, so essay topics are duplicated time and again by students searching for something about which to write. If you want something original, look at the development of U.S. history through a different lens. For example, use the development of railroads to explain the development of industry and regulation in the United States. Write about the depression that had hit the agricultural sector of the U.S. economy in the 1920s, well before it affected the rest of the economy beginning in 1929.
In a philosophy class, you can approach essays in any number of thoughtful ways. Incorporate history and philosophy by writing about the ethical dilemma that Harry S. Truman faced when he decided to drop the atomic bombs; focus on what may have informed his decision, and the moral and ethical ramifications that his decision had on society at large. Write an essay on how Islamic philosophers like Al-Kindi and Avicenna were informed by Greek philosophers.