prep school vs sports hall

prep school

noun
  • A private or public school intended to prepare its students to get into prestigious universities. 

  • A private primary school which prepares its pupils for the common entrance examination most commonly at the age of thirteen, and subsequent entry into public school. 

sports hall

noun
  • A building, or a room in a building, especially in a school, with facilities to play indoor sports. 

How often have the words prep school and sports hall occurred in a corpus of books? (source: Google Ngram Viewer )