Is your required science textbook on reserve in the Science Library? It's quite likely. We routinely look at the textbooks listed for science courses on the Oberlin College Bookstore website, and often decide to add the required textbook to the science library collection.
It is not guaranteed, however, and even if we do place the text on reserve your use is limited to 3 hours at a time and not for overnight use. So it does not take the place of owning your own book, with all of the benefits of being able to write in the margins, underline and highlight text to your heart's content, or read far into the night if necessary. We are just a bit more convenient than lugging around 1200+ pages of biochemistry (Voet and Voet is perhaps the heaviest text on reserve and one of the most popular for in-library reading).
Once you've found your textbook listed at the college bookstore, search OBIS and you'll see whether we own it and the course number for which it is reserved. Read all about reserve policies.