So I just bought a 83 rx7 the car is pretty crappy hut I only paid a couple hundred for it i drove it to school today and then was drifting around the parking lot and when I shut it off it won't turn on the battery has 12 volts the starter gets 12 on the big wire and no lights turn on and there's no power to anywhere on the ignition switch

 

Is your battery secure???

 

Jack the car up and bridge the starter B+ feed to the solenoid terminal. DO THIS WITH THE CAR IN NEUTRAL. If it cranks, you have an issue with your starting circuit.