RasMol is a molecular viewer available for Windows, Macintosh, and UNIX. This simple program allows you to view multiple molecules and allows you to manipulate the molecules.
Note: If you are in one of the school's computing facilities that is run by CIS it is most likely that RasMol is already installed on the computer. Look under the Util menu and see if it is there.
RasMol Links
RasMol - Class Application