well every kid is different, we have 10 children and ive found that with some kids, you just cant spank them, cause they just dont care, sounds like you have one of those. i found a good alternative to spanking little ones for discipline is to simply make them sit still, it drives them crazy, and probably will you too until they get used to it as a punishment but once they get it, it seems to work quite well as  a deterent. for litttle kids, a  few minutes of sitting completely still feels like hours. just imagine how it feels to us when we wait for the dr at their office. other things that worked for me were taking away favorite toys, little ones forget what they are doing a lot faster than older kids but normally just taking an item away and steering them away from the items or situation causing the problem also helps as well as directing them towards alternative activities when they are getting in to stuff. hope this helps.