Lately, I've been re-reading books that I had read as a teen, and I'm happy to say that thirty years later, I still love this book. The amazing thing (to me) is that House of Stairs is just as current today as it was back then. It is set in an unspecified, futuristic setting, yet now its seems very contemporary.
House of Stairs, like the Hunger Games series, is a story in which teens are pitted against teens. HoS is much simpler than HG, both in terms of setting and plot, but the four characters are very interesting as are the choices they make. This book says a lot about the human condition and reminds me of the themes in other books such as Lord of the Flies and the Butterfly Revolution (another great dystopian story about teens).
William Sleator's book was my first experience in dystopia, and I still love the genre. What surprised me, however, was that even though this book was supposedly written for 9 - 12 year olds, the author used *a lot* of cursing, and much of the scientific jargon towards the end would be very confusing. Even thought this is a short, simple read, I'd say it would be better for high school students.
All in all, I highly recommend this book.