Pre-service teachers from Texas and Indiana in the United States and from Queensland, Australia, observed the Moon for a semester and compared and contrasted their findings in asynchronous Internet discussion groups. The 188 pre-service teachers were required to conduct inquiry investigations for their methods coursework which included an initial Moon observation assignment, an Internet Moon discussion, and a final project. The Moon context was chosen for its motivating capability, its inherent interdisciplinary makeup, its inclusion in the National Science Education Standards, and its ability to be viewed worldwide. This study was of a mixed method research design and involved pre-service teachers' journals, summative reflections, Internet discussions, final projects, and the Lunar Phases Concept Inventory (LPCI). Analysis of the qualitative data was conducted through the exploration of patterns and themes that illustrated pre-service teachers' conceptual development, and the LPCI was administered as a pre/post assessment. We found that our project led to increased knowledge concerning the mathematics and science involved with understanding the Moon and its phases. We also found that it was beneficial to have Internet discussions with pre-service teachers from around the world, but it was not without its problems (e.g., coordinating schedules and lack of participation by some participants). We discovered that pre-service teachers' exposure to the new uses of technology for teaching and learning did not necessarily translate to their planning to adopt similar techniques in their own classrooms.