Why does a baby have about 350 bones, but his mom just over 200? Why are my bones hidden―not like a skeleton’s? And why does Mom say milk is good for my bones?Curious children learn most by zigging and zagging through the world, collecting information and connecting the dots.The Zigzag series is designed to introduce individual subjects to children and encourage them to zigzag down other paths to find out more. "I-can-read" print and photos clarify, illuminate, and pique interest. All books are in K1-appropriate, easy-to-understand language and addresses science-as-inquiry curriculum standards.