let’s play soccer for an hour ()school.in 还是at why?

let’s play soccer for an hour ()school.in 还是at why?

用at,固定搭配

at
in school指在上课，求学中。at school在学校里

应该是at school 吧。in后面一般加的是大地点，如in Beijing，in China等。而at后一般加小地点，如at home，at school。