By the 1920s, 4-H club work appeared in every county's plan of work. In 1927, based on the term 4H-Club work and the fourfold concept of head, heart, hands and health, Extension adopted the well-known 4-H pledge:
I pledge my head to clearer thinking,
my heart to greater loyalty,
my hands to larger service, and
my health to better living,
for my family, my club, my community, and my country.
Minnesota and Maine were the only states to add "my family"? to their pledges. The only other change, in 1973, was the addition of "world"? to the pledge.