<p>As other people have said, if you want to go over 18 units, you have to pay extra. It is about $1200 per unit I believe. However, if you maintain a 3.750 GPA, you can take up to 20 units without paying extra starting your sophomore year ([USC</a> Academic Achievement Award | Undergraduate Education](<a href=“http://undergrad.usc.edu/renaissance/achievement_award.html]USC”>http://undergrad.usc.edu/renaissance/achievement_award.html)).</p>
<p>I am currently a BME major in Viterbi and doing a theater minor, and I have found it possible to complete this 24 unit minor. The way I did it was by freeing up 8 units with AP BC Calculus, and then taking classes over the summer to free up more space my sophomore year. I also did go over 18 units my freshman year and payed the extra units. It is possible to do a minor with an engineering major, you just have to be creative and figure out a way to do it.</p>