Effects of parental involvement in home-based learning on children's vocabulary

This study examined the effects of parental involvement in home-based learning on children's vocabulary across two cohorts, using data from the Japanese Longitudinal Study of Children and Parents. Data from 2016 (Wave 2), 2019 (Wave 5), and 2022 (Wave 8), when vocabulary tests were administered, were included. The first cohort (N = 1,368) completed a vocabulary test in the third, sixth, and ninth grades, while the second cohort (N = 1,177) did so in the sixth, ninth, and twelfth grades. We employed a conditional latent growth model to examine whether parental involvement in Wave 2 predicted vocabulary changes. The results showed that parental involvement was not related to the slope. Additionally, we used a cross-lagged panel model to infer the causal effects of parental involvement. Results showed that parental autonomy support enhanced children's vocabulary, whereas parental control and direct instruction hindered it.