In physical education, students perform physical activities among their peers and teachers. Some students are highly skilled, while others are developing their skills, and some just do not participate at all. It has been questioned why one child would approach a new opportunity with excitement and enthusiasm and another child (with the same opportunity) would have anxiety and self-doubt. The Eccles' Expectancy Value Model was designed to describe and explain behavioral differences in choice, persistence, and performance of adolescents despite similar talent, opportunities, history of failures and successes across different achievement domains. In this study the Eccles' expectancy model was used to examine expectancies for success and subjective task value. The purpose of the study was to examine the influence of significant others on high school students' expectancies for success, task value, and motivation in physical education class. Specifically, this study examined perceived influence of significant others' beliefs on students': expectancies of success and task value (attainment, utility). Additionally, the influence of the students' expectancies of success and attainment and utility value on their intrinsic, extrinsic, and social motivation was explored. A total of 231 physical education students, ranging in age from 14-18 years old, enrolled in the 9th-12th grades from two high schools in the Midwest participated. Each student completed a questionnaire that assessed their expectancies for success, task value, motivation, and perceptions of significant others' beliefs. The researcher distributed and collected the surveys during physical education classes at each school. Multiple regression analyses were conducted in order to examine the influence of perceived parent, teacher, and classmate beliefs on the students' task value and ability expectations. Findings revealed that perceptions of parents' teachers', and classmates beliefs concerning ability expectations were positive predictors of the students own beliefs. Parents', teacher, and classmates' perceptions of students' attainment value for physical education were all significant predictors of students' attainment value for physical education. Perceptions of parents' attainment value emerged as the strongest predictor. Perceptions of parents' and classmates' utility value were significant in predicting student utility value for physical education with parents as the strongest predictor. Higher ability expectancies, attainment value, and utility value were related to lower intrinsic motivation. Higher attainment value predicted lower extrinsic motivation and higher utility value predicted lower social motivation. It was concluded that the perceptions of parents', teachers', and classmates positively predicted students' ability expectancies, attainment value, and utility value. Keyword(s): high school issues, physical education PK-12, research