Ответы будут более-менее краткие.
1. When they feel the coming of the age which makes them choose wisely, because later it'll affect on their own futures.
2. They usually go on some kind of professional courses.
3. No, some per cent of parents think children didn't grow enough to do that by their own, because they're afraid children can do "mistake".
4. For getting their kids better education level.
5. Because as politically will we choose, as better job we get.
6. It requires mind, patience, kindness, goodness and etcetera.
7. Because I like to give knowledge to young generation and english is one of my favourites languages.