Re: Work conditions as a Nanny
I was an Au Pair in 2009-2010. Basically, you and your host mom can work out your working conditions. I had friends who has similar work conditions as you (ie. they were paid hourly, lived out, worked less hours, etc.) and were on Au Pair contracts. It may not be totally on the "up and up" but it's common enough that you will be fine if that's what you agree to.
She will be contractually obliged to pay for at least half of the language course though (amounting to at least 120 hours), as well as at least half of your health insurance, as you will still on paper have an Au Pair contract. Make sure you iron out these details (as well as the costs) before you arrive. I suggest that you make sure she does pay for half of these costs, as they can really add up, and 2 thousand francs a month can run away quite quickly. Just my 2 cents.