Simultaneous bilingual and bicultural children who are schooled in the dominant societal language can acquire literacy in their home language through home literacy practices and weekend school. Twenty-eight Japanese-English bilingual–bicultural children (ages 9 to 14) attending English weekend schools in Japan were assessed using the standardized Test of Written Language (TOWL, 4th ed.). Their overall age-adjusted writing scores showed that most were on a par with same-age US peers. The parents’ responses to parental questionnaires revealed that the children’s regular attendance and enjoyment of weekend school, coupled with parental home support and access to plenty of appropriate English reading materials, helped to establish their English literacy. Nevertheless, the children attained different writing scores. Although many performed within the Average range, some scored either in the Above Average or higher range or the Below Average or lower range. Further analysis of these three groups of children revealed a strong relationship between reading practices and writing scores. Better writers tend to read frequently in English; they enjoy reading independently and voluntarily. These findings underscore the importance of recreational reading as an accessible and affordable means for developing home language literacy in bilingual and bicultural children in Japan.