Considering the immense efforts invested in Holocaust education in Israel and around the world, there is very little published research which looks at the impact of this education on teenagers' modes of understanding. This qualitative study addressed two questions: When adolescents learn about the Holocaust, what are the themes they see as central to an understanding of it? And, do these issues remain stable during the learning period? Forty-seven Jewish-Israeli teenagers (33 girls, 14 boys) were asked to write about their thoughts, feelings and attitudes about the Holocaust, both before and after participation in a Holocaust seminar that included a trip to Poland. The most salient themes that they wrote about at both time periods were: learning about the Holocaust, the evaluative theme, emotions, the link between the Holocaust and Israel and the Holocaust as the most horrific world event. We found little stability of thematic frequency and some stability in thematic meaning. Our results also show that the students reached cognitive, emotional, universal and culturally specific understandings from their Holocaust education.