Physics Playground is an immersive Virtual Reality (VR) application designed for educational purposes, featuring a virtual laboratory where users interact with various physics phenomena through guided experiments. This study aims to evaluate the application's design and educational content to facilitate its integration into classroom settings. A quantitative data collection investigated learning outcomes, related confidence, user experience, and perceived cognitive load, through a 2x2 within-between subjects setup, with participants divided into two conditions (VR vs. slideshow) and knowledge levels assessed twice (pre- and post-tests). A qualitative approach included interviews and a focus group to explore education experts' opinions on the overall experience and didactic content. Results showed an improvement in physics knowledge and confidence after the learning experience compared to baseline, regardless of the condition. Despite comparable perceived cognitive load, slideshow learning was slightly more effective in enhancing physics knowledge. However, both qualitative and quantitative results highlighted the immersive advantage of VR in enhancing user satisfaction. This approach pointed out limitations and advantages of VR-based learning, but more research is needed to understand how it can be implemented into broader teaching strategies.