What should I wear to a junior retreat at school?

I'm a 16 year old girl and I go to a Catholic school, so I am dressing modestly and decently since I am going to a monastery. But of course, I still want to look cute and be comfortable and not have something that I'll be sweating in. So far, I'm definitely wearing some jean shorts. But what top should I wear to still look cute? I know you don't know my school's rules, but do you think a modest flowy tank top would be too much skin? Thank you :)