Parents are considered world widely to be the best teachers. They teach us how to walk, talk and good manners. The development and education of a child is done the bestest by their parents.
Parents are mostly committed and involved in teaching their children. They are always ready to sacrifice apart of themselves  just for us. They shower great love and affection towards their child. Moreover, they show great patience while our upbringing. They are mostly involved in the education and development of their child. Their love passes a very good knowledge and lessons taught by them are unforgettable. Implicit learning occurs and children imitate their parents at every stage of life, wether thats the style of behaviour or the habits.
On the flip side, at the stage of adolescence child's friend is the best teacher. They prefer their friends advice more than their parents advice. They become notoriously rebellious in many cultures. So parents become more flexible and likely to be the partners of their child. Furthermore, good teaching is based on different attitudes, not on a single viewpoint. A teacher may have a wider knowledge but parents can easily clarify all those quarries that a teacher cannot, in a short period of time without hesitation. Even in the rapidly changing world, the scope of parents knowledge still has a great influence on their children.
I believe that parents are the best teachers since their lessons last forever. I consider that my parents give me very good advices when I need them based upon their life experiences.
@Honnieblossom