This qualitative study (n=17) uses a multiple case studies design to interrogate how and why students understand events contained within "heritage histories." By this I mean that the students are too young to have been involved in the events, but that their parents, grandparents, other family members, or other members of an affinity group (racial, ethnic, national, religious) to which they belong were involved. Prior research (e.g., An, 2009; Epstein, 1998, 2000, 2009; Peck, 2010; Wills, 1996) has demonstrated that students' racial, religious, ethnic, national, and socioeconomic class backgrounds impact and influence students' historical thinking, yet, as Barton (2008) astutely notes, "much more research is needed to illustrate the specific ways in which students of given backgrounds learn history both in and out of school" (p. 250). Therefore, I focused on the ways that three selected heritage groups learned about specific and meaningful heritage events in and out of their public school history classrooms: four Hmong students in St. Paul, Minnesota studying the Vietnam War; eight Chinese students in Los Angeles, California studying the Cultural Revolution; and five Jewish students in Chicago, Illinois studying the Holocaust. Through this work, I show that the students engaged in complex historical thinking as they worked to make sense of histories to which they all felt some degree of a heritage connection. While several of the students learned information at school that was dissimilar to what they had learned at home, they were able to critically evaluate both sources and develop narratives that incorporated the first and secondhand accounts of the past they had heard from their families with the official knowledge presented in their public school history classrooms. Additionally, by including these heritage histories in their curricula, the three teachers worked to also include their students' histories within the official knowledge of the classrooms. In so doing, the teachers sent a message to their students that the students' families' pasts are part of a history that has relevance and import beyond the three heritage communities; which tells the students that they, too, are important, relevant, valued members of the classroom communities and society in general. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]