Over the course of middle childhood, children's interest and beliefs about their own capacities for success in science often decline. This pernicious decline is especially evident among underrepresented groups, including girls, members of some racial and ethnic minorities, and children from lower socioeconomic backgrounds. The present research (N = 306, ages 6-11) found that while children lose interest and feelings of efficacy about their potential to "be scientists" across middle childhood, they maintain more robust interest and efficacy about "doing science." These patterns were confirmed in both longitudinal and cross-sectional analyses; effects were stable or increased across time and age. Mediation analyses revealed that the positive effect of action framing is partially accounted for by children's views that the group of people who do science is more inclusive than the category of scientists. These findings suggest that using action-focused language to encourage children in science is more inclusive and may lead to more science engagement across middle childhood than language that emphasizes "scientists" as an identity category. Implications for educational practices will be discussed.