I don't know how old your son is but my DS5 loves the book The Fantastic Elastic Brain. It explains how brains work and emphasizes that doing something difficult makes the brain grow and that making mistakes makes the brain grow, too. This really resonated with my son. Now when he makes mistakes, he laughs and says "I can feel my brain growing!" In addition to that book, we read lots of biographies of scientists, inventors and mathematicians that include descriptions of their failed experiments.
I second this recommendation! DS3 absolutely loves the book and refers to stretching his amygdala whenever he does anything challenging.
