According to attributional theory, when the application of effort leads to success we praise the achievement. Effort and ability, however, are seen as compensatory and thus, paradoxically, being praised can lead to attributions of low ability. Our study investigates whether praise, not for academic performance, but for social classroom behavior, would also incur attributional backlash. We examined whether prosociality relates to attributions of high effort and low ability, mediated by expected teacher praise and happiness. In adolescence, prosocial behavior is displayed more by females and aligns with femininity. We conducted an experimental vignette study with 324 German ninth graders to examine whether prosocial students experience a denigration of achievement via expected teacher reaction. Multilevel modelling showed that compared to nondescript students, prosocial students were judged to receive good grades as a result of effort and less due to ability, but this was not related to expected teacher reactions. Prosocial students were also judged to be more likeable and popular. Examination of gender-related outcomes showed that prosocial students were believed to be more feminine, but also more masculine than the nondescript student. Female prosocial targets were thought to be more typical, but not as occurring more frequently than their male counterparts. The results are discussed in reference to the paradox of praise. The limitations and implications of the research are discussed, particularly regarding female students’ achievements.