French tuition for young children (Geneva)

Hi

We're moving to Geneva in a couple of months and our children will be going to a bilingual (English/French) school. As neither of them currently have any French, I am considering getting them some joint lessons when we first arrive to help them settle-in more quickly. However, as they are aged 4 and 6 years old, age is a definite factor on how this would be work, so I would be interested to hear any thoughts, and/or recommendations as to good teachers.

Thanks very much

Sarah