A theoretical model based on path analytic logic was used to examine the relative influences of social origin and significant other influences on marital, fertility, and educational plans. Parents' education and the major family income-earner's occupation were used as measures of social origin; perceived encouragement by parents, teachers, counselors, and friends to attend college and close friends. college plans were included as measures of significant other influence. The effect of sex on the formation of educational plans was ascertained through a set of dummy variables. A proportionate, stratified, random cluster sample of 301 white high school seniors in rural Louisiana was used. Zero-order, first-order partial and multiple correlations of marital and fertility plans with educational plans were also computed for the total sample and each sex separately. Some findings were: statistically significant influences were produced by perceived parental and friends' encouragement and close friends' college plans; sex did not have a significant influence on educational plans, but had a notable effect on parental encouragement and marital and fertility plans; the relationship between marital and educational plans was significant; and a strong positive association between marital and educational plans for females contrasted with a significant inverse relationship between these variables for males. (Author/NQ)