I've done spins in a C152 during PPL training but only because the instructor happened to be an aerobatics guy. There's probably not a great learning experience but it's is very impressive to get to know what a spin feels like. I agree with those who say that spins usually happen at low altitude without any chance of recovery. Having experienced spins, pilots will probably take stalls and the golden rule about proper use of flight controls during slow flight much more serious.