Isn't this what the new Do Not Disturb feature in IOS6 addresses? http://www.apple.com/ios/ios6/

Also, all iPads have the switch above the volume button as a mute button already for notifications like this.

(Note: yes, I know most people have changed this setting (back) to be an orientation-lock, but this guy's new to iPads so I'm assuming he didn't change the setting)