chalk talk vs coaching

chalk talk

noun
  • An informal lecture on an academic subject. 

  • A music hall act in which a performer makes chalk caricatures whilst reciting a monologue 

coaching

noun
  • The process by which someone is coached or tutored; instruction. 

  • The operation of horse-drawn coaches, especially as a business. 

  • Relating to horse-drawn stagecoaches, also to railway carriages (or coaches). 

How often have the words chalk talk and coaching occurred in a corpus of books? (source: Google Ngram Viewer )