chastening

Dear Sir, We have read the articals about home schooling as we recently started this with our children. (age 7, 8 12 and 15) homeschooling is still rare in the Netherlands so therefore we found your information very usefull and we would like to get you permission to use your information for our family and friends who consider homeschooling as well. The part of chastening is understood also very well but in the a discussion item between me and my husband is untill what age we should use spanking (with rod) . So far we are using this for all our 4 children in case needed . Please can you advise..Many thanks for your advise, Kind Regards Sanne