When I do the laundry, usually I fold and sort the clothes for the kids, and then hand them each one stack at a time and they put them away. They have gotten quite good at doing it this way, and I have not seen a reason to change it.
But this last week, I folded Bean's clothing and stacked them into one stack without sorting them into groups. He came into the laundry room while I was still folding, grabbed his stack, and went off to put them away. I went after him to warn him that I had not separated the clothes for him yet, only to find him sitting on the floor separating them into neat little piles of pants, shirts, socks and underwear on his own. I was so impressed!