Middle School 和 High School 都是中学吗？那初中和高中怎么区分？ - 知乎 senior high school (or senior high): a school in the US and Canada for children aged between 14 or 15 and 18 middle school: 1) a school in Britain for children between the ages of 8 and 12; 2) a school in the US for children between the ages of 11 and 14