I think it depends on the child and their age. I have a son who boards and his 'day' starts at 6.45am with lessons from 8.30am through to 5pm - although they have 2hrs every afternoon from 1.30 -3.30pm for sports and 'after-school' activities - and then back for a last double-lesson.
He then has 2 hrs of down time to go for supper, play pool/table tennis/swim go to the gym etc with his friends - or just hang out in his dorm until prep, which is from 7 - 9pm - lights out at 10pm (phones are not allowed during the day and are also taken away at 9pm!)
He also has Saturday school and then, after lunch, an afternoon of matches.....he's 14 and in Y10....
He absolutely loves his school - as do all his friends - and I know he's very happy, academically challenged and mentally and physically healthy from all the activities and sport but what do others think.....is it all too much?