Put on your socks and shoes -- and don't forget your ears

We're going on a listening walk. Shhhhh. Do not talk. Do not hurry. Get ready to fill your ears with a world of wonderful and surprising sounds.

When you were a baby, you didn't have any teeth at all. Then as you grew, your teeth started to come in. First one, then two - and finally, twenty teeth in all

But you won't keep these teeth forever. First one, then two, will wiggle loose. Maybe you've lost some of your first teeth already. When the little teeth come out and the big teeth come in, everyone can see - you're growing up.

Night and day, whether you're asleep or awake, your heart is always beating. Read and find out how your heart works and how to keep it healthy.

What happens to food when you eat it?

Read and find out about your digestive system and how it turns food into energy your body can use.