Using data for seventh grade students from the Seoul Education Longitudinal Study of
2010-2012, this study examined differences in academic achievement gains between private and
public elementary school graduates during their middle school years. Results show that private
elementary school graduates were more likely than public elementary school graduates to come
from advantaged families. In addition, private elementary school graduates outperformed public
elementary school graduates on mathematics and English achievement in seventh grade. However,
there were no significant differences in academic achievement gains between private and public
elementary schools graduates, after controlling for other variables. Further, we found no
significant differences in friendship between private and public elementary school graduates nor
did we find evidence that friendship had a direct impact on students’ academic achievement.
These findings suggest that the reason why private elementary school graduates do not
continuously exceed their public school counterparts in terms of academic achievement throughout
middle school is not, at least, due to problems in friendship.