Teacher professional development and classroom resources across the curriculum
Teacher professional development and classroom resources across the curriculum
Learner Express: Modules for Teaching and Learning

Scientist Elissa Levine of the NASA Goddard Space Flight Center discusses how the composition of soil is important in determining its properties, such as flow rate and nutrient availability. Flow rates can be demonstrated by pouring water through containers containing sand, silt, and clay. The sand allows the water to flow through quickly, while the silt and clay hold it longer. The right combination of all three allows water and air to flow through the soil, appropriately trapping and releasing water and nutrients, making them available for plants and microbes. Run Time: 00:02:16
Unifying concepts: Rate compares one measured quantity with another. D. Water circulates through the crust, atmosphere, and oceans (water cycle).