This qualitative case study examines the nature of a dual language preschool teacher's instructional practices and extratextual talk during shared-book reading practices with two different genres of books in Spanish and English. Specifically, I explore the interpersonal, ideational, and textual features of one teacher's talk in English- and Spanish-language medium book reading activities as she shares and discusses a storybook and a nonnarrative informational book with her emergent bilingual preschool students. The study is guided by the following research questions: (1) How are teachers' instructional and discourse practices functional for interacting across different genres and in different languages? (a) What is the nature of teachers' instructional practices across different genres and languages? (b) What discourse features are reflected in teachers' extratextual talk across different genres of text and in different languages? Four read alouds, in which a teacher read 1 English narrative book, 1 English informational book, 1 Spanish narrative book, and 1 Spanish informational book, were videotaped and transcribed. The teacher, Ms. C, is a native Spanish-speaking Latina female who is bilingual in English and Spanish. Using a systemic functional linguistic framework, data were coded for the academic discourse features in Ms. C's extratextual speech and analyzed to examine how Ms. C's language was functional for bridging the academic discourse of storybooks and informational texts in English and Spanish. In terms of Ms. C's discourse features, findings of the study reveal that book genre determined the organization of Ms. C's message, the role that she assumes in the read aloud, and the knowledge and content that she navigates for children in her speech. With regards to Ms. C's instructional practices, the language of the book/instruction determined differences in the vocabulary, narrative, nonnarrative, and print knowledge targets that Ms. C discusses, the instructional strategies that she uses, and the translanguaging practices that she implements to navigate the text for children. The results of this study inform the field with regard to ways in which teachers apprentice children in different genre-specific registers of academic discourse at the initial stages of schooling. These findings are unique to those already documented in the field since little research describes teachers' genre- and language-specific instructional practices across narrative and informational texts in bilingual preschool classrooms. Several important implications are suggested for teachers' instructional practices around narrative and informational texts in Spanish and English target languages. [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.]