A vital component of achieving climate neutrality in the future involves bolstering energy efficiency measures in educational institutions and improving the overall knowledge on sustainable solutions. To achieve fruitful outcomes, the active involvement of various stakeholders, such as managers, teaching staff, and students, is indispensable. By implementing energy-efficient building systems, advancing the use of renewable energy sources, and incorporating sustainable practices into the curriculum, educational institutions can decrease their environmental impact and conserve resources for future generations. Active participation from all stakeholders, including managers, teaching staff, and students, is essential for the success of these efforts. Providing students with a comprehensive education on sustainability equips them to apply this knowledge in their future professions, thus contributing to a more sustainable society. To gain insights into the existing state of sustainability within educational systems, a comprehensive study of educational institutions was undertaken. To assess and compare schools’ sustainability, a composite indicator was developed. The study’s findings reveal that the implementation of mandatory and optional measures can lead to a substantial reduction in primary energy consumption by 39% and greenhouse gas emissions by 34% in educational institutions. The average abandonment costs for mandatory measures are 5.87 EUR/kgCO2/year, but the average value for optional measures is 33.80 EUR/kgCO2/year. It is suggested demonstration projects be implemented in institutions where specialists in RE, mechatronics, building engineering systems, and environmental technologies are trained by showcasing technologies needed for the transition to climate neutrality.