Annette Lareau coined the term “concerted cultivation” to describe the cultural logic of a distinctive middle-class parenting pattern. I explore whether concerted cultivation as practiced in Japan exhibits unique patterns in response to distinctive characteristics of the nation's education system (i.e., standardized compulsory education with high-stakes educational selection in secondary education). Using nationally representative longitudinal data on third-to sixth-grade children (N = 30187) through growth curve models, I show that college educated parents shift their focus of parenting practices (measured by four aspects) from providing diverse experiences to narrower academic preparation as the time for lower secondary education approaches. Using multivariate analyses with an additional wave of data in seventh grade, I further demonstrate that “unequal childhoods,”––the accumulated disparities in adult-led structured experiences––lead to unequal success in the transition to junior high school education, a critical period of preparation before the mass educational selection (i.e., high school admissions).