The Ship to: box represents the camper you are building the care package for. If it's the first item you're adding to your cart, you will need to add their name (or add name) before clicking Add to Cart. After that you can select their name from the Ship to: box for each additional item. If you're building packages for multiple campers just add additional names as you go.
Works kind of like a sling-shot. Once in the air the flying motion causes it to start screaming (whatever you call what monkeys scream?) adding to the fun. You should hear the UPS trucks leaving our Center when they hit a bump, all the flying/screaming animals come to life!