Mobile Phone for children

We can often find articles in a newspaper on children who are prohibited from bringing their mobile phone to school.
The official view of my company is as follows
“All users including young people will be able to use a mobile phone’s filtering service and to limit usage to a voice call and a GPS. In addition, we provide lessons on how to operate mobile phone and to show the dangerous possibilities.”
The point is that parents don’t watch children’s phone usage. For example, children buy a Play Station (game) and use it under parental supervision. Parents understand the various aspects about the Play Station. There are no chances for parents to get to know the service’s children use.
It is recommended to have a lecture on how to operate it and what are the dangerous for both parents and children.