This study focused on effects of high-ability programs on students' achievement emotions, i.e. emotions that students experience that are associated with achievement activities. Participants were students in grade 4-6 of primary education: 218 students attended full-time high-ability programs, 245 attended part-time high-ability programs (i.e. external pull-out class). Using propensity score matching, they were matched to a control group of 189 students from regular education with similar cognitive abilities. The respondents filled out questionnaires on their achievement emotions three times during a school year. Results of multilevel analyses showed that students who attended full-time high-ability programs did not report more beneficial achievement emotions compared to similar students in regular education. In contrast, students in part-time programs experienced more positive and less negative emotions during the part-time program compared to the control group in regular education. No differences in longitudinal developments throughout the school year were found between the groups.