The American government and families attach great importance to the 4H youth development project, which has become one of the most important contents of agricultural technology popularization in the United States. It has been widely developed in American states and spread to more than 80 countries around the world. 4H is the abbreviation of hand, head, health and heart. This is an educational concept that emphasizes the harmonious development of "hand, brain, body and mind", extracts knowledge from nature and daily life, develops potential, and then creates a positive outlook on life in life. The slogan of 4H education is "learn by doing", the motto is "keep improving", and the oath is "I am willing to cultivate me with sincerity, for myself, for my 4H club, for my country and for the whole world: to use my thoughts with a sound mind; Sound mental development personality; Sound hands improve life; A sound body to serve the society. " The badge is a four-petal green clover, and each leaf has a white letter "H", which symbolizes that 4H is as vigorous as alfalfa, ubiquitous and ever-present; Even four leaves mean synchronous and coordinated development, not favoring one side over another.

At present, the American 4H headquarters is located in the National Institute of Food and Agriculture of the US Department of Agriculture. With the support of 600,000 volunteers, it trains more than 6.5 million young people every year, guides them to learn through practice and teaches them life skills. The project has the following characteristics: First, the purpose is clear. Cultivate young people's lifelong skills and help them choose the right life and career. Including: learning public speaking, conducting scientific experiments, organizing meetings, choosing a healthy lifestyle, serving local communities, acquiring social skills and living independently, cultivating professional interests, cultivating problem-solving ability and critical thinking ability. Second, there are various activities. Teenagers aged 5- 19 can join and organize various societies to carry out activities in camps, schools and off-campus, generally twice a month. The 4H project emphasizes learning by doing and active participation. The third is to play the role of volunteers. 4 hours is organized in the form of clubs. 4 hours agricultural extension workers mainly recruit and train volunteers, and volunteers carry out club activities to train and guide young people. Volunteers come from parents, teachers, technicians and so on. And it must be strictly screened, requiring people to be decent, honest, reliable in background and have professional knowledge in a certain field. Fourth, the content of the activity is attractive. They are all interest clubs. Teenagers of different ages and hobbies can choose their favorite clubs. Providing personalized topics is the most attractive part of 4H education, and a topic can contain many topics that inspire young people to learn and develop their imagination.