<p>I personally am not a big fan of prep courses, but if you think it is worth it, go for it.</p>
<p>Still, surely a prep course won’t take up your entire summer? o.O You want to maximize on your time. Absolutely volunteer and/or find a job/internship. Take on-line courses or classes at the local CC, etc.</p>
<p>Some colleges (e.g. Princeton) specifically ask about what you did each summer during high school. You’ll want to be able to put down something more substantial than a PSAT prep course.</p>