Since the coronavirus pandemic began in early 2020, K-12 students have faced unprecedented upheaval in many aspects of their daily lives. Their schools abruptly closed and almost overnight their classes shifted to remote learning, a largely unfamiliar instructional model for them and their teachers. To learn more about the impact on students' mental health, the EdWeek Research Center surveyed 2,000 high school students in grades 9-12 between January 29 and February 11, 2021. The research center compared results from the student survey with high school educators' responses to similar questions that had been included in a late-January 2021 survey exploring their perspectives regarding the pandemic's effect on K-12 education. This report examines results from the winter 2021 EdWeek Research Center surveys of high school students and educators to gauge the pandemic's impact on students' mental health. ["Supporting Teacher Well-Being in a Time of Crisis" is included as a section written by Brooke Stafford Brizard.]