middle school vs teach

middle school

noun
  • An educational level or stage between primary school and secondary school. 

  • A school which crosses the traditional divide between primary school and secondary school. 

teach

noun
  • teacher 

verb
  • To pass on knowledge generally, especially as one's profession; to act as a teacher. 

  • To pass on knowledge to. 

  • To cause to know the disagreeable consequences of some action. 

  • To cause (someone) to learn or understand (something). 

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