Tex, I love the story of your DS and his giant. I don't know what to say, with respect to resizing, though. Are you saying your DS is tinkering with the concept of conservatism? Are you familiar with that classic test with the glasses of water?
My story about my DD's drawing was a feeble attempt to say she is past egocentric thinking. Maybe I should have used a different example (I was pretty excited she would think to accommodate my view from across the table lol). Egocentrism is one aspect of her thinking that is conspicuously absent.
Okay, maybe these are better examples: DD on the phone with her grandmother says, "Granny, do you want to talk with your baby son? Okay, hold on. DADDY! Your mom is on the phone and she wants to talk with you! Ok, Granny, here's your son, John." Or, DD is playing with a barbie in one hand and a mermaid in the other (this particular barbie has articulated legs and came with a bicycle). DD has barbie say to the mermaid, "Hi! Wanna go for a bike ride with me?" Mermaid answers, "No thanks. I have a tail. I'm going to swim lessons now."
My original question was whether it was possible for a child of 3 to be in concrete operational thinking. So I contacted an expert, David Elkind. He said yes, it's possible if the child's IQ is over 150.
I'm not ready to state DD's IQ is over 150, but it has been a lot of fun reading up on Piaget. It's led to reading about Vygotsky, supervised play, and his concept of "scaffolding." Interesting stuff.
