A sudden shift to distance education during the COVID-19 pandemic in Turkiye strained teaching and learning activities, placing K-12 teachers in a novel context with challenges and opportunities to investigate. This study explores the teaching experiences and opinions of K-12 teachers during the COVID-19 pandemic, focusing on challenges, advantages, and suggestions. Search queries were executed in leading databases (DergiPark, ULAKBIM TRDizin) to locate potential studies. Twenty-two studies meeting the predetermined inclusion and exclusion criteria were subjected to a rigorous and iterative thematic analysis using the qualitative meta-synthesis approach. The results revealed significant challenges categorized into ten themes: shortcomings in technology and infrastructure, student motivation and engagement, technology literacy, and social and emotional well-being. The results also highlighted key advantages of distance education in eight categories such as learning improvement, flexibility and convenience, and digital tools and resources. Additionally, the study identified valuable suggestions that contribute to the success of distance education, such as adapting curriculum, increasing access to technology, strengthening internet infrastructure, providing teacher training and support, developing engaging and interactive instructional materials, and improving communication and collaboration between students and teachers. The study results inform the development of evidence-based practices and policies that can support K-12 teachers in providing quality online education during times of crisis.