Despite the metaverse having been increasingly designed, developed, and applied to education, critical issues regarding the lack of truly immersive learning environments, custom tools, clear instructional design, and inconvenience of using the platform, and ethics and privacy concerns exist. This study aimed to design and develop a 3-D metaverse platform, "Learningverse" to support teaching, social, and cognitive presences. Learningverse combines the key features of an immersive learning environment with avatars that mirror the real users, rich social interactions among avatars, custom tools that allow users to construct or create their own artefacts, and a low threshold for users to join the metaverse on an ordinary computer with a webcam and without having to wear a VR headset. A usability test was conducted to understand students' perceived teaching, social, and cognitive presences in a scenario called "Assembling the Solar System," which had an immersive learning instructional design embedded in Learningverse. The study involved 36 postgraduate students in a course on the innovative design of interactive learning environments. The results showed that students perceived the three presences positively. Discussions were made, followed by design principles for the educational metaverse based on this study. Finally, future work was explored.