The problem that was addressed in this study was that the academic needs of English Language Learners (ELLs) were not being met in biology classes in high schools in the local district because teachers were not consistently facilitating instruction using the required strategies of student discourse and collaborative structures. The purpose of this qualitative study was to explore teachers' successes, challenges, and need for supports when using the required strategies with their ELLs. Knowles' theory of andragogy and Shulman's theory of pedagogical content knowledge guided this study examining how the adults' learning of the required strategies impacted their ability to implement them effectively. The research questions asked about the teachers' successes, challenges, and need for supports when using the required strategies. This study employed a basic qualitative inquiry design using semi-structured face-to-face interviews of 11 high school biology teachers. Analysis of the data using a five-phase cycle, revealed that teachers were successful implementing the required strategies when they built positive classroom environments and relationships, modeled with examples, and put multiple structures into place. They faced challenges addressing students' negative feelings and addressing students' lack of motivation. The identified needs included access to ongoing support and the ability to observe other teachers' instruction to improve their own practice. This study may contribute to positive social change by providing administrators and teachers with information they can use to improve facilitation of the required instructional strategies which may close the achievement gaps between ELLs and English-speaking students. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]