Spring is in the air and birds are building nests all over town. Learn all about the wide variety of nests you can find in Jennifer Ward's book, Mama Built a Little Nest. Identify which bird built the nest using the National Geographic Kids Bird Guide of North America. And birds aren't the only animals that build nests. Check out A Nest is Noisy by Dianna Hutts Aston to explore the incredible world of nests.