Benchmark 4C
The Physical Setting: Processes that Shape the Earth
Grades 3-5, page 72

Rock is composed of different combinations of minerals. Smaller rocks come from the breakage and weathering of bedrock and larger rocks. Soil is made partly from weathered rock, partly from plant remains--and also contains many living organisms.
 

NSES Content Standard D 
Earth and Space Science: Properties of Earth materials 
Grades K-4, page 134 
Soils have properties of color and texture, capacity to retain water, and ability to support the growth of many kinds of plants, including those in our food supply. 

NSES Content Standard D 
Earth and Space Science: Structure of the Earth system 
Grades 5-8, page 160 
Soil consists of weathered rocks, decomposed organic material from dead plants, animals, and bacteria. Soils are often found in layers, with each having a different chemical composition and texture.