Hello, we went through the process last year. BTW, they will invite you for a preview to show the classroom layout and what to expect in early December, a month or so before actual assessment. There are a number of "workstations" - dinosaurs, train track, cars, farm animals (I had none at home), drawing table etc. They let children to choose what to play with and teachers observe what they do. After kids are shown a book and read a story and asked queationa about it. Eg. What is in the book ? "moon" "what else in the sky" "Stars" "do you know a song about stars" "Twinkle, twinkle". There are also toys around the room but kids are not supposed to take them - my son was interested in a robot but was quickly stopped. I have been preparing him and on the day he was not shy, very confident first in into the room, he was the only child to be interested in sitting down and drawing and very good at sharing and playing in groups.
My son is a summer baby and bilingual so had a speech delay at the time of the assessment (2.5ys). We got an answer that he was not ready but they would be happy to invite us for assessment in the future. I have now deferred his assessment to 5+ to improve his chances as I have realised it makes a huge difference at this age. In his current school (he is in pre-reception) there is a boy who moved from DP in year 1, August baby and was not coping. He has now been moved one class down and thriving.
We had an option of 3 nurseries: Rosemead in WD, Parkgate in CJ and the Woodentops/the White House in Streatham/Balham - easy commute from Dulwich via South Circular (Long story but our place in the waiting list for DUCKs never came up, despite me registering at 3 months pregnant and his hald-sinbling graduating from it a few years back, so I had to search for 3+ place...) After much contemplation I have chosen the White House as they have very good results: they year 11+ got 75% of their choice - 3 boys going to DC, 1 Trinity, 1 has 3 scholarship offers and still deciding between DC, Emmanuel and Royal Russell's. The class is max 12 ppl. Girls go to JAGS, Sydenham's, Seven Sisters. A few years back one pupil went to the Harrow on pre-test. I have never heard about this school as they didn't do much PR (though were featured in top 10 independent in last year's Sunday Times overview and school agencies regularly send kids here - a Turkish ice-skating junior champion is the latest addition) Deputy head was previousely a teacher in Westminster UnderSchool... despite small school size (2 forms this year but previously one form only), good sports results. Interestingly, half of pre-reception is summer babies - which I think tells a lot. As one of the parents said "They are kicking above their weight". Lovely family like school atmosphere.