One of the most effective ways students can learn about plants, their parts, and their needs is to be involved in the growing process. Provide pots, soil, and seeds for children to plant. If available, a container made of see-through plastic will enable children to observe the entire plant, including the root. Experiment with different amounts of light or water to see which plants excel in the growth process. Preschools 4 All suggests giving children a squirt bottle for them to water plants which provides them with a fine-motor challenge in addition to the science lesson.
Plants require light in order to make the food necessary for life. You can help children remember this fact with a hands-on experiment. First-School suggests the teacher and children place a paint can lid or flat piece of wood on a patch of grass with a rock on top so that it won't be moved. The class can check on the grass underneath the wood every few days to observe what is happening. See if children can figure out why the grass underneath the wood is losing color.
Children will learn patience and plant anatomy as they help grow a sweet potato in a jar. Insert 4 toothpicks in the middle of the potato to help the plant rest on the edge of a glass jar without touching the bottom. Place water in the bottom of the jar so that the bottom of the potato is submerged. As water evaporates, add more to keep the level the same. According to Preschool Rock, some roots should develop after a few days, and after a few more, leaves will grow out of the top. In a few weeks, children can plant the sweet potato in a pot, keeping roots under the dirt and leaves above.
Students can witness how plants need water by using celery and glasses of water with food coloring. An adult should cut the bottoms and tops off of celery stalks, and then cut into pieces that can be fully submerged in glasses of water. Place 3 drops of food coloring in each glass. Science Fair Adventure suggests using red or blue food coloring for this experiment. Then at regular intervals, such as 2 hours, 4 hours, 12 hours, 24 hours, and 48 hours, cut into the celery to see the results. Students should find that over time the celery draws water through the entire plant as shown by the coloring.