Through the grant “Virtual Campus for Life Long Learning” (NUV, 2007), we have gained experience in the design and building of a virtual island or “sim” in Second Life for the purpose of education. This paper discusses the virtual representations, tools, context and spaces used in courses. While SL can replicate the classroom lecture, it gives further opportunities for interactive and active teaching as learning activities can be in dispersed and diversified virtual spaces. These are transient learning spaces because participants, activities and representations are in frequent change. Designing transient learning spaces raises different challenges and opportunities from the traditional physical classroom. Challenges include enabling new users to know where to go or how to behave. One opportunity is the ability to design and develop a new space for each course. This article will help the teacher and “sim” designers to recognize the factors of designing effective transient learning spaces.