<p>OP hasn’t mentioned in which class her S earned the D. At the state university I attended, second semester calculus was the weeder class for many would-be CS majors, even those fortunate few who had BC Calc back when dinosaurs roamed the earth. The students I know who have had trouble with a CS program tended to struggle with the math part of it. (Lin Alg can be a similarly tough course.) Students who programmed by the seat of their pants in HS can be in for a rude awakening when it’s time to start doing things algorithmically.</p>
<p>S has TA’d AP/first-year CS courses and says the biggest struggle folks have is learning to integrate math into solving the programming problem.</p>
<p>Totally agree w/Marian’s post, too.</p>