Data gathered via random sampling from white, unmarried high school seniors (143 males and 158 females) in rural Louisiana were utilized to test the following hypotheses: (1) social origin will affect significant other influence; (2) social origin and significant other influence will affect educational plans and will be largely mediated through significant other influence; (3) social origin and significant other influence will affect both marital and fertility plans; (4) marital and fertility plans will be related to educational plans; and (5) sex will not affect significant other influence or educational plans but will affect marital and fertility plans. Survey responses were analyzed in terms of the following variables: Social Origin (father's and mother's education and major family income-earner's occupation); Significant Other Influence (encouragement from parents, teachers, guidance counselors, and friends and peer modeling); and Marital, Fertility, and Educational Plans. Results indicated: (1) the "modeling" mode of influence was especially sensitive to social origin factors; (2) there was agreement with prior research concerning the mediating role of significant other influence; (3) the effect of others was a crucial source of influence on educational plans; (4) there were no decidedly different processual variations between males and females. (JC)