Each person has their own opinion about parents are the best teacher or not. Personally, I agree with the idea that parents are the best teacher, because I believe some factors make them are the best.
On the other hand I agree that parents are the best teacher in order to teach daily life activity. For example when I was a kid my parents teach me how to pray, how to take a bath, how to brush my teeth, how to eat by myself, and etc. Parents are more beneficial to help children reach their future.
However, there are some reasons againts previous idea. Firstly, parents are less skilled at teaching skill. In any case, parents usually can present only viewpoint of the world, while good teaching should be based on different attitudes. Secondly, parents can be negative impact to children and some parents also teach children how to commit crime. Many incidents show that children will be thief if they see their parents are thief.
In conclusion, the things we learn from our parents are important to our lives and their contribution are much more important than traditional academic teachers and that's why I agree with this opinion.