The job itself is very interesting, it's nice to meet a French family willing to know more about your language and culture. I worked there for 1 year in Paris during my exchange year there. I was working 8 hours a week, so it was perfect to fit with my classes and my activities!
What I liked too about working at Speaking Agency is the workshops they organize to know more about children and how to handle specific situations.
I also made some friends at their monthly Wine & Cheese which I recommend you to go!
The pay is good too.