During the fourth quarter in science, students will investigate the components of soil (sand, clay, and humus) and explore the relationship between soil and plant growth. Students will create their own compost bags. This activity enables them to observe the decomposition of organic materials over time. Students observe and read about earthworms to learn about their connection to plant roots and soil. The students also conduct tests that enable them to observe and compare such properties of soil as odor, appearance, and texture. Phenomena such as settling, water content, and soil consistency are also explored. These observations are then related to plant growth. By observing root growth, students learn about the role of roots in keeping the plant anchored and upright. Students apply what they have learned to investigate a sample of local garden soil.