The Hitchhiker's Guide to the Galaxy: Hitchhiker's Guide Series, Book 1 (by Douglas Adams)

They hitch a ride on one of the Vogon constructor ships that demolished the earth, are ejected into space, and picked up by The Heart of Gold, a new spaceship powered by the Infinite Improbability Drive, which has just been stolen by two-headed, three-armed Zaphod Beeblebrox, President of the Galaxy. They journey with him to Magrathea, the planet where, millions of years earlier, the Earth was constructed as part of a giant, organic computer designed to come up with the question to the answer to the question of life, the universe, and everything. Get it?

Originally written for adults, this has become very popular with bright middle-schoolers and high-schoolers who enjoy the snarky British humor. Some passages will go right over the heads of many readers, but for those who get it this pioneering classic introduction to the genre of British sci-fi humor can become an obsession, leading to Terry Pratchett, Monty Python, and others. The cliffhanger ending will drive them crazy, of course, but fortunately the whole series is available, so they can quickly satisfy their need to continue.

Despite the drinking and innuendo, many parents like to see their kids enjoying this because the humor is intellectual and verbal, rather than the usual American pratfalls and potty jokes. Many lines have become catchphrases to the initiated, a quick way to find those of like mind and interests: saying "42!", "Life, don't talk to me about life," or Don't panic!" to a roomful of young adolescents is one way to sort them out quickly.