Wheelie

the wheel spins one way. you tip the other.

hold to gas and the front comes up -- in the air, throttle is the only steering you get

A spinning wheel pushes back on whatever it is bolted to -- Newton's third law, not a video-game trick. Gas the rear wheel harder and the frame you are sitting on pitches the other way, nose up; ease off and it pitches back down. On the ground the tyres fight that push and mostly win. In the air there is nothing else to push against, so the throttle is the only thing steering which way you are facing when you land -- hold it through a jump and you keep rotating backward past flat; let go and you rotate the other way.

Concepts: torque, angular-momentum, balance.

An interactive you play with one thumb, on Wundr.