<p>Are they useful at all....as reference/refresher books for a new college student who is continuing a course of study in the sciences? I've been telling myself for four years that we should hold on to them "just in case".......but my child has never not once cracked one open beyond the last day of that particular class and they're just gathering dust. I know I won't get nearly what we spent to buy them if we sell them back, but we'll get something......or we could pass them along to a rising Senior and save them a few dollars.</p>
<p>Might as well keep them, for relevant things they will be studying in college.</p>