Actually, the coffin you dug up has a mannequin dressed like a teacher in it. You take the teacher and put her in the classroom near the desk. After you do that, you place numbers on the black board and solve the 3 equations. If you do that, you get the gun. Then you play the Rifle Range game, use the key from that to go into the door behind the Rifle Range counter, and then use the jackhammer on the exposed brick area in the drywall. After that, you will be in a little kid's bedroom. *#thecreepynessintensifies*