A game that teaches everyday social skills by Lawrence E. Shapiro Ph.D. Hidden Rules (or Hidden Curriculum) is a term used to describe unwritten social rules and behaviors that most of us seem to know without ever being taught, such as respecting those in a position of authority, acknowledging others' personal space, speaking at an appropriate volume, paying attention to body language, and more. This fun card game will help children learn and practice 40 hidden rules in friendship situations. 2-8 players.