In recent years, concerns about indoor air quality (IAQ) in educational settings have intensified, particularly following the COVID-19 pandemic. The need for high-efficiency ventilation systems that balance IAQ with minimal energy consumption has become increasingly pressing. However, retrofitting existing buildings with mechanical ventilation solutions poses significant challenges, primarily due to spatial constraints limiting the installation of duct systems. To address these challenges, a novel stand-alone ventilation system equipped with a heat recovery unit was developed and tested. Designed for direct installation within classrooms, this system bypasses the need for duct networks. Nevertheless, this approach introduced new challenges, primarily related to noise mitigation. A tailored demand-controlled ventilation strategy was also developed to optimize the system's performance in educational settings. This research aimed to evaluate the performance of this innovative ventilation solution and assess its ability to overcome the identified challenges. To achieve this, the ventilation units and control strategy were installed and tested in a functional classroom. Indoor air quality was monitored providing valuable insights into the system's effectiveness. The results demonstrate a substantial increase in teaching hours with acceptable air quality ranges, underscoring the potential of this novel ventilation solution to improve IAQ in educational settings.