If you live in the UK and you think smacking children is a bad idea, you might want to respond to this consultation:
http://www.dfes.gov.uk/consultations/conDetails.cfm?consultationId=1494 Deadline 10 August (next Friday).
You can do an online response and you don't necessarily have to fill in all the questions, so it needn't necessarily take long.
More info/background at:
http://www.childrenareunbeatable.org.uk/pages/info.html