This is fun! we're all best friends and we're all playing: supporting children's synchronous collaboration

A device for exercising the lungs by forced inhaling or exhaling comprises a mouthpiece and a valve assembly incorporating a valve housing unit having a gas inlet port and a gas outlet port both communicating with a cavity in which a movable valve body is received and which valve body has a first passageway for directing gas between the inlet and outlet ports and a second passageway for directing gas between a by-pass port and the gas outlet port. The relative amount of gas passing through the gas inlet port and through the gas by-pass port is determined by the position of the valve body and can be regulated by moving the valve body. The device also includes means for monitoring the flow of gas passing through the gas inlet port and preferably the length of time of that gas passage, and means for counting sequential inspirations or expirations of the user during the exercise.