Final answer:
The Civilian Conservation Corps (CCC) was a program that employed young men to work on environmental projects during the New Deal era. It had a significant impact on the development of state and national parks.
Step-by-step explanation:
The Civilian Conservation Corps (CCC) was a program created during the New Deal in the 1930s. It employed young men between the ages of eighteen and twenty-five, as well as veterans, to work on various environmental projects such as reforestation, park maintenance, and erosion control. The CCC employed over three million workers and had a significant impact on the development of state and national parks, planting billions of trees and improving the overall environment.