When I was in primary school I was taught the days of the week from the order Sunday to Saturday, so Saturday was the end of the week iyswim. But since I left primary school Sunday has always been the end of the week and a new week started on a Monday.
DS has just learned his days of the week in school now too in the same way and if either me or dp say it in order from Monday to Sunday he corrects us.
Why are children (I am just assuming it is all children and not just me or ds) taught the days of the week this way and not from Monday to Sunday?