COVID-19 has had a substantial impact on almost every field including the education sector. Due to the requirements for social distancing, the pandemic has provided an impetus for change in the education sector; technology-based sustainable education platforms not experienced previously have become essential. This research aims to propose flexible strategies to mitigate challenges of COVID-19 pandemic in the education sector of an emerging economy: Bangladesh. A total of 16 challenges and 19 flexible strategies were identified based on stakeholders' inputs and literature review. To evaluate the flexible strategies, a methodology based on Pareto analysis and a revised rough-decision making trial and evaluation laboratory (rough-DEMATEL) method is proposed. Findings reveal that in the context of the COVID-19 pandemic, 'Maintain social distancing and health protocol,' 'Enhance the communication and collaboration among students and teachers,' 'Financial incentives from government,' 'Utilize modern technologies for digitizing the entire education system,' and 'Know how to engage students in an online environment' are the vital strategies that must be implemented if education continues through E-learning. Because the current pandemic situation is a new experience for many individuals around the world, this study helps to recognize the challenges and to propose effective strategies to solve these challenges so that education does not become stagnant.