kid stuff vs puerile

kid stuff

noun
  • Something that is easy to do or easy to understand. 

  • Something done by, used by, or characteristic of immature people, especially children. 

puerile

adj
  • Childish; trifling; silly. 

  • Characteristic of, or pertaining to, a boy or boys; compare puellile. 

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