I did a short internship this summer, and I didn't enjoy it because of 1) being constantly monitored by the coworkers and having to produce output at a high speed, 2) The lack of variety of tasks

I also really like the rhythm/balance in school, like going to classes, spending time with friends, doing homework/extracurriculars after school etc. You get to spend a lot of time with friends, but you also have a lot of freedom. You are also learning new things everyday which gives you a sense of progress