Tough times in Minnesota in the 1930s brought economic depression, droughts, and clouds of grasshoppers that destroyed crops across the state. Extension entomologist H.L. Parten and county agents conducted grasshopper-baiting demonstrations with poison bait provided by state funds. In 1939, one-fourth of all Minnesota farmers spread the bait and avoided an estimated $12.6 million crop loss during a time of 40-cent-per-bushel corn. Extension’s response to the grasshopper plague helped create a research-based approach that farmers, state officials and Extension would use to tackle future problems, such as the 1980s farm foreclosures and the 2007 bovine tuberculosis outbreaks.

As early as 1937, southern Minnesota farmers were experimenting with soybeans as a new oil crop. Extension tried to hold off promoting this until it was clear whether it was really marketable. The farmers insisted, however, and Extension listened. By the 1940s, soybean variety demonstrations were among Extension's regular agricultural programs. University soybean geneticist Jean Lambert developed new varieties that made Minnesota a leading soybean state. Extension introduced the varieties to farmers through field days, publications and the mass media. Farm income from soybean production alone was huge, more than the entire University budget in the 1950s.

As World War II ended, farmers were concerned about how to effectively market the abundant crops they were producing. In 1946, the Research and Marketing Act gave funds to Extension nationally for marketing programs. Minnesota used its share to develop three projects: improving efficiency in marketing and distributing eggs and poultry, improving market quality of milk, and developing and marketing frozen foods. In 1950, Extension added a consumer marketing project to let people know where they could find plentiful food supplies. This helped producers get a better price for their products. Consumer marketing specialist Eleanor Loomis used radio and television to broadcast Extension information.

In 1935, a St. Louis County home demonstration agent predicted that schools would serve hot lunches just as they hired teachers and bought books. As early as 1911, Extension had set up a hot lunch program in the rural schools, complete with bulletins and recipes.

By 1940, hot lunch programs had been established in more than 200 Minnesota schools. In the 1940s and ’50s, Extension nutritionists taught school lunch staff around the state how to transform surplus commodities into healthful meals.

After the Great Depression of the 1930s, many rural and low-income people were sleeping on cornhusk mattresses. In 1941, the U.S. Department of Agriculture had a large amount of surplus cotton, bought up from Southern cotton producers. Extension agents in 84 counties accepted the offer of cotton and ticking and organized mattress-making centers in village halls and county fair buildings. They helped 70,000 Minnesota families make their own mattresses and comforters. Total cost of supplies was 88 cents per mattress and 33 cents per comforter. With this program, Extension helped solve an economic problem in one part of the country and assist low-income farm families at home.

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.

As early as 1926, 4-H participants were contributing to conservation and environmental work. The Conservation Leadership Camp at Itasca, begun in 1934, continued for 51 years. Each year, 200 youth learned firsthand about wildlife and land conservation. Taking their knowledge back to their hometowns, they planted thousands of trees, started windbreaks, built bird feeders and seeded forest tree nurseries. The seedlings the early campers planted in Itasca State Park are now towering red pines that park visitors still enjoy. 4-H environmental work goes on today in county camps and programs.

President Roosevelt established the Rural Electrification Administration (REA) in 1935, but the U.S. Department of Agriculture left it up to individual groups to organize. On their own, local groups asked Extension for help. Two months after REA went into effect, Meeker County Extension agent Ralph Wayne and former agent Frank Marshall organized the first rural electric cooperative in Minnesota. This two-year work in progress became the first demonstration site in the nation.

In 1940, Extension sponsored nine farm and home equipment shows across the state showing how electricity could be used in operating farms and modernizing rural homes.