Over at Amateur Gardening we discovered this awesome tutorial for how to take the stone from your next avocado and turn it into a plant to grow and care for. The initial process is super easy only requiring toothpicks, a glass of water, and later a pot with some potting soil. Read the article linked below for the full details on this easy and fun gardening tip.
A word of warning: Avocado trees can grow very large if not properly pruned or kept potted. They require warm climate so if you are very far north with a freezing winter they need to be moved indoors during the winter. Keep near a sunny window and they can be a houseplant and may even fruit, although fruition of edible fruit can be rather rare and may take several years.