In 1985, the National University of Mexico (UNAM) created a series of updating courses for high-school level teachers, both as an answer to an explicit demand of the teachers themselves, who asked for “fresh” information in their fields, and as an effort to improve the general level of undergraduate students, whose grades in the entrance examinations to the University had been secularly decreasing for years. To date, three “packages” of intensive 50-hour courses have been offered (during the three summer vacation periods) and Astronomy has been present in all of them. However, it should be mentioned that this presence was due only to the personal interest of the director of the project, since the subject “Astronomy” is not included in the official programs. In the following, we present a brief description of the courses and some interesting results.