From Longman Dictionary of Contemporary Englishmiddle schoolˈmiddle school noun [countable, uncountable] 1 SESa school in Britain for children between the ages of 8 and 122 SESa school in the US for children between the ages of 11 and 14
Examples from the Corpus
middle school• Linda first saw Red at a middle school volleyball game.• In middle school, your children would rather attend your execution than have you attend their field trip.• My own work on middle school teachers provides some support for this view.• This does to, but in the back they all the covenant kids listed together, all the middle school kids.• Another letter from the middle school was about a visiting theatre group and asked for money as well as a tear-off slip. 