Metaview is an interactive tool that helps to teach concepts related to nested 3D coordinate systems, especially in the context of defining and establishing views of 3D scenes in common graphics APIs like OpenGL and Direct3D. We describe the context in which nested coordinate systems arise in the study of graphics programming, then we relate the common conceptual difficulties students typically experience when studying and trying to put this material into practice. We then describe the role that metaview plays in helping to overcome these problems. Space allows us only to describe its core uses in these areas; several of its additional features are briefly listed at the end. Metaview is packaged with a set of built-in 3D models used to demonstrate major concepts. In addition, external and/or student-programmed models are easily imported into the tool. Metaview can be run anywhere, anytime using Java Web Start. The latest released version of the tool can be executed from http://people.eecs.ku.edu/~miller/JOGL/metaview.jnlp. We are currently working on a port to OpenGL ES targeted for portable smart devices such as tablet computers.