baby sitting in Paris

Hello!
We're a French family with 2 boys: a 8 year-old and 9 year-old.
We're looking for a cheerful, authoritative, responsible English native speaker to take care of our kids during weekdays after school starting September 2016.
Main tasks would be : picking them up from school and supporting the home work then bathing and serving dinner.
The week job will be : Monday, Tuesday, Wednesday, Friday: 4:30 PM to 07:30 PM
If possible : Wednesday : all day (if not, I have another solution).
We live in Paris (4 stations from Montparnasse, line #13)
Hope to hear from you soon :-)
Clarisse