I realized too late that my top CS program wasn’t challenging enough. If I did it again, I would have taken some grad classes and lean heavily in to upper division math classes, or maybe go for a physics minor, but I was so interested in coasting during my early 20s. Many classmates did that and got much more out of their undergrad (one classmate double majored in math and became a professor at UIUC after grad school).
One of my favourite memories branching out was taking an intro to abstract algebra course where the professor was in his 90s and a WW2 vet which left a lifelong impression. Was such a fantastic course and essential to honing my proof writing skills.
