A pre-fabricated concrete slab system and method have matching rectangular slabs with cooperatively fitting male and female type connectors which fit adjacent to each other in a checkerboard fashion. The slabs include spaced reinforcing rods extending longitudinally and transversely therethrough. In at least some of the slabs, the rods' distal ends protrude outwardly away from one or more side edges of the slabs to form a plurality of male connectors. Correspondingly, at least some of the slabs include a plurality of corresponding female sockets on one or more sides thereof, each female socket receiving a corresponding male connector when dropped therein. Through interconnection of corresponding female sockets and male connectors by steel reinforcing bars extending in both the longitudinal and transverse directions, a continuous tension reinforcement is established between adjacent slabs in both the longitudinal and transverse directions.