Eating Disorder Prevention in Schools Act of 2020 This bill requires local educational agencies (LEAs) participating in the school lunch or breakfast programs to include goals for reducing disordered eating in children of all sizes in their local school wellness policies. Such LEAs must also include registered dietitians and licensed mental health professionals in the development, implementation, and periodic review of such policies. The bill also requires the Department of Agriculture to provide information and technical assistance to LEAs, school food authorities, school health professionals, and state educational agencies for use in establishing healthy school environments. Such technical assistance must promote eating disorder prevention and encourage screening for such disorders.