<p>There was a thread a while ago about a similar subject:
<a href=“http://talk.collegeconfidential.com/parents-forum/1289172-big-savings-u-s-students-open-source-book-program.html[/url]”>http://talk.collegeconfidential.com/parents-forum/1289172-big-savings-u-s-students-open-source-book-program.html</a></p>
<p>There are free text books for a number of subjects, but they do not seem to have gained much traction (beyond the instructor who wrote the book), except for a certain introductory CS book that seems to be fairly commonly used (although it was not free in its earlier years).</p>
<p>Even if the course does not use the free book, the existence of the free books means that students have an alternate source for an explanation of a topic that may be difficult to understand in the book assigned for the course.</p>