This exercise is designed for young children (K to 3) to teach the different parts of a plant (root, stems, leaves, flowers, fruit, and seeds), the basic functions of each part, and to show that tiny microscopic organisms (“germs”) can cause each part of a plant to become diseased. The lesson shows children the importance of understanding what causes plants to be sick and the need for scientists called plant pathologists to keep plants healthy. The lesson should last approximately 20 min followed by a 20 min laboratory. It requires easily available materials and minimal preparation time.