I am constantly impressed by my kids and how quickly they learn, but what really impresses me is watching them reach certain levels of mental development. My daughter is four now so she’s picking up new facts and abilities all of the time, but it’s the bigger things that get me. She is starting to think abstractly and it’s amazing to watch. Just a few months ago she was an entirely different person than she is now, and it’s all because she’s understanding things in a way that she couldn’t then. It’s like watching hundreds of little light switches come on, and with each one her eyes become a little more piercing, a little more aware, and a little more observant.