The flight instructor reported that the student pilot was taking off following a touch and go landing and was about 5 seconds into the climb when the engine lost all power. The flight instructor took control of the airplane and attempted to restart the engine to no avail. He declared an emergency and chose to conduct a forced landing to an upsloping field. The airplane sustained substantial damage to the fuselage and left horizontal stabilizer. The fuel tanks were intact. A Federal Aviation Inspector, who conducted a postaccident examination of the airplane at the scene, reported that the left fuel tank was completely empty, and the 25-gallon capacity right fuel tank was found about ½ full. The fuel selector was in the “Off” position. No other preaccident mechanical failures or malfunctions with the airplane were found that would have precluded normal operation. The flight instructor reported that they had purchased 20 gallons of fuel prior to the flight. They flew the airplane to another airport where they did a touch-and-go landing, before flying back to their home airport where they did another touch and go landing. It was during the climb following that touch and go landing when the engine lost all power. The flight instructor could not recall which fuel tank was selected at the time of the power loss. Given this information, it is likely that the left fuel tank was selected and was exhausted of fuel during the takeoff, which resulted in the total loss of engine power and subsequent forced landing.