I primarily taught high school and undergraduate math courses with the occasional graduate math course, and undergraduate cs course tossed in as well. Since much of undergraduate math teaching is really just the high school teaching of yesteryear, I don't make much of a distinction. Anyway, most of what is here will be Mathematica and, for what it is worth, I am gradually adding materials. In this era of restricted access and paywalls, I always liked professors who put lots of free materials on the their websites. Finally, my "keys" occassionally have errors which either I or my former students would catch and I would correct in class. In my defense they were often made at 4am in a rush and I would remind my students that not many faculty let you keep all of your quizzes and exams (except the final) and provide you with a both a handwritten and Mathematica key.
Precalc
Calculus 1
Calculus 3 (multi)
ODE's