Have you ever tried saying something to a kid only once and checking to see if they understand it? Well, they don't. You have to say the same thing at least 5 times. Then they
may start looking at you like they're beginning to grasp the idea. I've read that a child has to taste something new at least 5 times before they decide they like it. So, the same thing must be true for understanding what you say. If you ask them to repeat what you just said, they can. But, really understanding what you just said is a whole new different story.
This is true for any kid. No matter how well nourished or how bright their parents say they are, they will not, no matter what, understand something you just said only once.
Why do you think ads come on TV sooooo many times a day? Because they are aimed at kids. They know these children will only get the idea after days of watching TV.
So, if you're a frustrated mom or teacher who thinks your kids have some kind of problem because you have to repeat EVERYTHING several times, don't worry, that's the way they were programmed. They are ALL that way. Relax!