The problem addressed in this qualitative multi-case study was that high school and college students who transitioned to online learning during the COVID-19 pandemic experienced increased mental health issues due to the lack of social relationships caused by social isolation. The purpose of this qualitative multi-case study was to examine high school and college students' perceptions of the mental health effects they experienced during the COVID-19 pandemic due to a lack of social relationships caused by social isolation. The data collection for the study included surveys, interviews, and artifacts. Using purposive sampling, five high school students who transitioned to online learning during the pandemic and five college students who transitioned to online learning during the pandemic were recruited as participants. Thematic analysis was used to identify codes, patterns, and themes. Themes identified stress due to isolation, restriction, and anxiety as a challenge for high school participants, while adjustments to online learning changes, mental health challenges, and inability to foresee the future were themes identified by college participants. Additionally, themes of adjusting to virtual communication and spending time with family were the focus of high school students' social relationships during the pandemic, while minimal social interaction and lack of professional support were themes for college students. High school students recommended interactive and engaging online activities for education professionals if an online transition to education was re-implemented, while college students recommended advanced tools, guides, class times, activities, and smaller online groups or classes. This study provided recommendations for school tools that may help families promote a healthier routine at home. [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.]