developmental vs instructive

developmental

adj
  • Related to development. 

noun
  • A trainee flight controller. 

instructive

adj
  • Conveying knowledge, information or instruction. 

noun
  • A case in the Finnish and Estonian languages. It expresses the means or the instrument used to perform an action. 

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