When I used to spank mine, I used a wooden spoon. Department stores have that one with the really long handle. I'd stick that thing in my back pocket & carry it around with me everywhere.
Lived in California for a bit... Policeman behind me in line at the Post Office gave me the whole "appearance of abuse" lecture. I told him that when he was responsible for raising my kids, that he'd get to choose how they were disciplined... until then he could bugger off.
There does come a point when spanking is no longer appropriate... because once they get a little bit older there are other "incentives" to not get into trouble... like removing of their outdoor play privileges... no bike... no after school visitors... no phone... While the whole grounding thing seems really "leave it to beaver," it is pretty effective.
*edit* I would have been A-OK with the school administration spanking my kids... when they were younger. Or calling me to the school to administer the spanking.
*edit again* Leave it to CNN to characterize spanking as "beating your kids" *rolls my eyes*