Negative consequences: 1. Extreme child-centered theory. It is not conducive to the inheritance of human cultural heritage, and even the most basic knowledge such as reading, writing and arithmetic cannot be mastered by children, resulting in poor academic and moral standards of students and affecting the quality of education in primary and secondary schools in the United States. 2. Progressive education almost abandons discipline and exercise because it advocates child-centered theory and emphasizes students' initiative, freedom and individuality. 3. The focus of teaching has shifted from traditional teachers to children, who are the core of teaching. Therefore, progressive teaching denies strict, precise and strict discipline. It denies the role of some disciplines in cultivating and training the mind. 4. Many schools have abolished the strict academic performance standards and examination scoring system in traditional schools.