From Caterpillar to Butterfly Big Book is a comprehensive exploration of butterflies, and this oversize edition (18 1/4 by 15 1/4 inches) is perfect for sharing in the classroom. This is a perfect beginner's guide to the mystery of metamorphosis. A caterpillar comes to school in a jar. The class watches the caterpillar each day as it grows and changes. Soon, it disappears into a hard shell called a chrysalis. Then the chrysalis breaks, and a beautiful butterfly flies out of the jar!