A network to share best practices for children with special needs
I absolutely feel manners instills self confidence in children. Anyone who behaves with good character traits feels good at the end of the day-they feel successful. My children are immediately rewarded with verbal praise when I hear them use their good manners. My daughter is especially good at this saying "please" and "thank you", along with "good morning", etc. Just this past Sunday, she got into her carpool and said "good morning Dr. so and so". I heard about her nice manners from the mother. That evening, I told her how proud I was that she used good manners-this feeling of success and goodness makes her feel worthy and good about herself and therefore gives her self confidence.
For the latter part of the question, I feel manners can and should be taught early on. Personally, my kids hear about manners as soon as they can understand language. I have heard my 2 year old say "thank you mommy" (more like "sank you mommy") and he uses please when asking for something (e.g. "cookie please"). It's never too early to start!