<p>Many (not all) LACs have small math and/or CS (or combined) departments that may not offer many math and CS options at the junior and senior level (or any at the graduate level, if you are very advanced in math to the point of likely wanting to take graduate level math courses). You need to check the course catalogs to see what courses they offer, and the schedules to see how often they are offered.</p>
<p>Yes, at a big research university, you may find an introductory CS course with 700 to 1,000 students, taught by one faculty member and a bunch of TAs. But if that same big research university followed the LAC model and taught 700 to 1,000 students with only faculty in 25-student sections (3 per faculty member), it would consume about 9 to 14 faculty members just for 28 to 40 sections of that one introductory CS course, leaving much less faculty time to teach other CS courses, including junior/senior level CS courses (and there are typically three to six frosh/soph level CS courses that tend to be large). Math can have similar trade-offs, perhaps even more so because math departments need to teach a lot of non-math majors who need math courses for majors in sciences, economics, engineering, and business.</p>