This talk presents the results of an astronomy teacher training program (TTP) for primary education in Chile. The TTP focused on Sun-Earth-Moon topics and was implemented in two modalities: an intensive in-person summer school and an extensive 5-month hybrid course. Participants took content knowledge and attitudes pre- and post-tests. Some assignments and a final focus group were also analyzed. The results show an increase in astronomy content and attitudes scores in both modalities, but with a greater impact on content knowledge in the intensive case and on attitudes in the extensive one. Differences are also observed depending on the astronomy topic or the attitudinal dimension analyzed. The implications of these results and teachers' perceptions after their participation are discussed.