Hi, I'm new to this site and would like to offer my little experience.
I live in Rolle and there are two very good facilitiies here , my son having attended one of them and friends children having attended the other.
Rolle is only 15 minutes by car from Nyon and its tiny so once you are here, you don't have another 20 minutes to find the places.
Places are limited and you will have to check for availability but both facilities have a fabulous garden.
La Barcarolle (hope I have spelt it correctly) and Le Cygne (not sure of the spelling but it means the swan.
I don't know if they do mother and toddler classes but they do childcare which I have to say La Barcarolle I was very impressed with.
please note they are both French speaking but La Barcarolle has so many English speaking kids that some of thier staff speak English.
As for mother toddler sort of gathering or courses I am also looking for one for a friend who has just moved to Nyon and who doesn't know anyone and I thought I would find her some places to meet other mother's with small children. If anyone has any information on this sort of service I would also really appreciate the info.