The human hand is made up of four fingers and one thumb. This month's "Home Connections" activity will help students understand the importance of the thumb for doing simple, everyday activities. Most primates (humans, apes, and Old World monkeys) and some other animals have opposable thumbs. Humans can move their thumb farther across their hand than any other primate. This article provides some simple activities students can try both with and without using their thumbs to help them develop a new appreciation for these digits.