They accept kids as from 16 mths old. You need to call them first. Both the La Cite Noble and Metro City have playgroups on weekday afternoons or Saturday mornings. Weekday afternoons are easier to join and Saturday ones are very full. Normally have to wait for places until bigger kids leave and go for N1 so to spare places.
I phoned them when my boy was 1 yrs old and left my phone no. to them to wait in the queue. Of course we also applied for N1 and was admitted after the interview. My boy waited and then successfully joined the Saturday playgroup since Jan 09 when he reached 18 mths.
Now classes are 1hr (Metro City) for $110 each or 1hr 15 min (La Cite Noble) for $150 each. Classes are offered in package of every 2 months.