This is very significant to soil use and management. Soil color can serve as an indicator of many soil properties. Organic matter content, drainage condition and aeration are soil properties related to color which are of interest to farmers. A gritty feeling indicates a sandy soil. Crumbly feeling indicates a silt.
Sticky feeling indicates clay.
Have students collect different samples from various locations around your school. Compare the soils from the different locations as to the amount of sand, silt, clay and organic matter.