Last yeat I got my 14 year old son a RWS 34 Panther in .22 caliber. Mounted a Centerpoint 3-9x 32mm scope on it. Very accurate set up, and the .22 caliber does a number on small game. See attached links on scope and rifle. I highly recommend both of them.
http://www.pyramydair.com/p/rws-34-panther-air-rifle.shtml
http://www.pyramydair.com/cgi-bin/accessory.pl?accessory_id=1662