Raise and Sell Farm Animals and Chickens
Look around you, and you'll get the sense that many families are seeking ways to go back to the basics. They're re-learning the skills of self-reliance, such as gardening and building structures, and in their quest to be more independent, they're buying and raising farm animals. It's not just rural families either, but urban families are raising what they can (and what they neighbors will allow) in their own backyards. This demand for farm animals requires a supplier, and that can be your family.
Raising and selling small farm animals and birds is a great idea for a family business, if you have enough land to raise them on. However, it doesn't require a lot of land. For example, goats only need 1/4 acre, and chickens require less. These small scale farm animals are needed by families who themselves only have a small plot of land, such as a backyard.
Most children enjoy working with animals, and so will yours. They'll learn responsibility, major life issues when they reach an appropriate age (such as where goat kids come from) and economics at the same time. Sell animals when they're young for others to raise, and sell others when they mature. You'll also have opportunities to sell related products, such as eggs or milk for animal consumption. (Note that it's illegal to sell milk for human consumption without becoming a formal dairy business.)