Switching inputs on the classroom projector
If your Mac supports AirPlay Mirroring, an AirPlay Mirroring menu appears in the top menu. Turn on mirroring by clicking on the AirPlay icon: and then selecting the room number where you want to connect.
To turn off AirPlay Mirroring, select “Disconnect AirPlay Display”
iPad or iPhone with iOS7 & iOS8
You need an iPad 2 or later or an iPhone 4S or later