With the end of the most recent period of emergency remote teaching (ERT), there is an opportunity to evaluate how ERT facilitated and perhaps accelerated the evolution of instructional practices, particularly regarding the use of educational technology. The question remains whether the accelerated rate of technological adaptation produced durable changes in instruction. Hence, this qualitative study contributes to the growing body of research literature regarding the needs of teachers as diverse adult learners of ERT, the best practices in professional development for high school teachers during ERT, and the extent to which teachers' experiences during ERT inform their use of educational technology after the pandemic response ended. Eighteen tenured teachers from the same suburban high school participated in focus groups and follow-up interviews. They acknowledged the old and new challenges ahead regarding assessment and academic integrity in the age of artificial intelligence, but they differed in tactics and strategies for how to meet these challenges. With regard to educational technology, teachers used it sporadically prior to the COVID-19 pandemic, but they embraced it to deliver instruction in the ERT setting. They used it to design project-based assessments for the ERT setting. They continue using technology-enabled ERT instructional strategies post-pandemic, but they generally use educational technology more purposefully. Teachers feel more technology is not inherently better for students and educators. Teachers recognize educational technology as a set of tools intended to meet the diverse needs of students, but it is not always the best tool. Students need a variety of engaging learning experiences. Thus, teachers now use video to deliver asynchronous instruction for students with special needs and have students make their own in lieu of class presentations. They integrate interactive apps into their lessons to collect assessment data and to engage students who are otherwise reluctant to participate. They use versatile learning management systems to distribute resources, collect student work, and provide meaningful feedback. Regarding professional development related to educational technology, the teachers shared their professional development experiences, namely opportunities and resources that the school district allocated formally as well as those that teachers pursued informally. They reflected on the focus, format, and effectiveness of the district's professional development efforts to date and identified opportunities for school leaders to pursue in the future. Lastly, they expressed a desire for sustained and purposeful professional development. Teachers described effective professional development as those learning experiences that prioritize teacher autonomy, authenticity, relevance, collaboration, ample time to practice, and the need for trust and more flexible alternatives. [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.]