After 25 years of playing with children from 6 weeks to 16 years old, the following tools may help you on the road to initiating fun, especially with school-agers. Place your index fingers on the bridge of your nose, hands facing in as if praying, insert thumbnails under front teeth, and flick teeth outward as you twist hands on nose. It sounds like you cracked your nose, plus a little play-acting is helpful to enhance the effect. You're going to guess three changes the other person makes in the way they look.
Kids really do know how to listen when the scene looks like it's worth playing.
Maximum Activity Play. Follow their lead as much as possible. Good leadership with children includes genuine followership. Even the best activities from the best books only come alive when good leadership is at play. So remember, you're competing with powerful electronic media.