Wonderful! Thank you for sharing :)
I did something sort of similar with my high level (elementary) kids last year. I showed them Picasso's Maya-in-a-Sailor-Suit painting, but I didn't tell the kids anything. I simply asked them, "is it good?" I gave them a few minutes to decide if it's good/bad and why. (This was sort of a writing class). Most of them said it was bad and explained what was so bad about it, but then when I told them it was Picasso they all changed their minds, LOL. Anyway, it started up a good discussion and I think it went well!