Adopting a genre lens informed by Systemic Functional Linguistics (cf. Halliday & Matthiessen, [Halliday, M. A. K., 2004]; Martin & Rose, [Martin, J. R., 2008]), this paper explores the text-structural and lexico-grammatical choices that second language (L2) writers of German make in personal letter writing. Close analysis of two student texts from an advanced, content-based, college-level German course help to illustrate more and less successful realizations of a complex letter task. Both genre and register analyses of these texts show how letter writing can offer L2 learners opportunities to practice evaluative (especially affective) discourse and develop understanding for different subject positions. Key text-structural and linguistic patterns are summarized in a writing rubric that teachers can use to guide and assess students' personal letter writing. As the writing task at the center of the study is based on the young-adult novel, "Damals war es Friedrich" (1961), and is situated within an instructional unit on German memories of the Holocaust, the analysis additionally contributes to ongoing dialogue concerning the teaching of the Holocaust (cf. Hirsch & Kacandes, [Hirsch, M., 2004]), by focusing on students' engagement with the content material through a linguistic perspective.