THE HEROS STUDY (HEALTHY ENVIRONMENTS STUDY) IS AN INTEGRATED RESEARCH, EXTENSION, AND EDUCATION PROJECT TARGETING PRESCHOOLERS AND THEIR FAMILIES WITH A LONG-TERM GOAL OF REDUCING CHILDHOOD OBESITY RISK (PROGRAM FOCUS AREA: CHILDHOOD OBESITY). IT ADDRESSES TWO CENTRAL ENVIRONMENTS FOR YOUNG CHILDREN, HOME AND PRESCHOOL, VIA DEVELOPMENTALLY APPROPRIATE, EVIDENCE-BASED, AND INNOVATIVE SOCIAL MARKETING STRATEGIES. BUILDING UPON OUR CURRENT LONGITUDINAL STUDY WITH PRESCHOOLERS (THE LEAP STUDY), HEROS SEEKS TO IMPACT YOUNG CHILDREN'S HEALTHY BEHAVIORS BY INCORPORATING OUR SUCCESSES IN IMPROVING WILLINGNESS TO TRY NEW FOODS AND MOTOR PERFORMANCE IN PRESCHOOL, AND AMPLIFYING THESE EFFECTS BY ADDING A POWERFUL FAMILY COMPONENT. WE WILL TARGET LOW INCOME AND LATINO FAMILIES LIVING IN RURAL COLORADO, WITH THE HIGHEST PREVALENCE OF OBESITY AND HEALTH DISPARITIES. THE PROJECT WILL DEVELOP TECHNOLOGY-BASED MOBILE APPLICATIONS TO IMPROVE PARENT-CHILD INTERACTIONS RELATED TO HEALTHY EATING AND PHYSICAL ACTIVITY. IN A QUASI-EXPERIMENTAL CONTROLLED DESIGN, THE IMPACT OF THE ESTABLISHED FOOD FRIENDS PRESCHOOL PROGRAMS (CONTROL) AND THE COMBINED PRESCHOOL AND FAMILY-BASED PROGRAMS (INTERVENTION) WILL BE COMPARED TO DETERMINE EFFECTS ON: 1) CHILDREN'S WILLINGNESS TO TRY NEW FOODS AND DIETARY INTAKE; 2) CHILDREN'S MOTOR PERFORMANCE AND PHYSICAL ACTIVITY; 3) QUALITY OF PARENT-CHILD INTERACTIONS RELATED TO EATING AND ACTIVITY; AND 4) THE HOME ENVIRONMENT. UNIVERSITY STUDENTS WILL GAIN VALUABLE RESEARCH EXPERIENCE AND FUTURE EDUCATORS, HEALTH CARE PROFESSIONALS AND EXTENSION AGENTS, WILL RECEIVE CHILDHOOD OBESITY PREVENTION TRAINING. THE PROJECT'S LONG TERM GOAL IS CONSISTENT WITH USDA'S GOAL OF IMPROVING THE NATION'S NUTRITION AND HEALTH BY PROMOTING THE DEVELOPMENT OF HEALTHY EATING AND ACTIVITY HABITS IN CHILDREN.