Relations between parental reports of children's interests related to science and opportunities for science learning were examined longitudinally in 192 children between ages 4 and 7 years. Science interests were tracked during 1-year periods (ages 4-5, 5-6, and 6-7) and were more prevalent among boys, particularly prior to age 6 years. Gender differences did emerge in terms of frequencies of opportunities for science learning during all 3 years. Longitudinal path analyses tested relations between children's science interests and their opportunities for science learning. Our data suggest that early science interests were strong predictors of later opportunities to engage in informal science learning, whereas the opposite pattern (early opportunities predicting later science interests) was not found. Young girls' expressed science interests led parents to subsequently increase opportunities for science learning during the following year. Although boys followed this pattern early in the study, over time boys received similar levels of science opportunities regardless of their interest. Bases for gender differences in early science interests and implications for later science learning in school are considered. (Contains 5 tables, 2 figures and 3 footnotes.)