Our boarding school is 70/30 split and the day students run the gamut, from the ones who basically live on campus, are involved in all sorts of activities from sports to clubs and do not leave till late in the evening to kids who mostly come for classes, have serious extracurriculars and/or social life outside of school. At least for the first two years, it very much depends on how far away you live and how willing are your parents to pick you up on your schedule vs theirs (and potentially other siblings/family members). By junior year most of our day students drive so have much more freedom to come and go, and are more likely to still be on campus late from my observation. My child is a boarder with quite a few day student friends, mostly from his sports teams and the club he is heavily involved in.