I did on three different occasions. First, to keep myself from having to take two weed outs when I was actually enrolled in college (took them at cc immediately after graduating high school). Those were physics and calculus. Second, I needed a class for honors college requirements and wanted to put as low of effort into satisfying them as possible. That was an equivalent to freshman composition. Third, I added a second major and a certificate late in my college career (year 3/4), so taking a class in the summer freed me up. I also didn’t want to take that class during the semester. That was creative writing.

If you’re planning to work full time over the summer I’d suggest not taking a lot of classes and taking classes that should be fairly straightforward for you. I worked full time two of those summers, and it was exhausting. I took writing courses those summers because they didn’t require a lot of self study or attending lectures.

My sibling also took summer classes. They applied to college as undecided so they had to take a couple of classes to get on track with the major they ended up choosing. But they only did school those summers and now are doing an internship.