Do you have sound on other apps? Do you have keyboard clicks when you type on iPad?
If no, you may have system sounds muted. The switch just above the volume control on the upper right hand side of your iPad can be programmed to either mute system sounds or lock screen orientation. If it is programmed to mute, simply moving the button in the opposite direction will restore system sounds and you'll see what it does by moving it and looking at your iPad screen. If is says mute, you're done and you should have sounds.
If, when you move the button it says lock orientation, you can double tap your home button to open the Task Bar (most recently used apps). With your finger swipe those apps all the way to the right and the very last icon on the left will be a mute icon. Touch it and you'll restore system sounds. Tap your home button once to close the task bar.