We explored longitudinal effects of a two-generation preschool programme on receptive language scores in children (n = 78) at age 10 years, living with low income. Scores at four time-points, programme intake, exit, age 7, and age 10 years were measured using the "Peabody picture vocabulary test" (3rd ed.). Effects of culture (Aboriginal, other Canadian-born, and recent immigrant), and gender of the children were explored. Between programme intake and age 10, scores improved significantly, F(3, 75) = 21.11, p < 0.0005. There were significant differences among cultural groups at all time-points except age 10. Scores differed significantly for girls, but not boys, at age 10, F = 5.11, p = 0.01. Recent immigrant boys reached the Canadian average, while girls were two-thirds of the standard deviation below average. Early intervention programmes must include a focus on the unique circumstances of recent immigrant girls; supportive transition workers in schools are one recommendation.