Geology (42) With an upgraded X-Ray Diffractometer, equipped with computer-controlled goniometer, digital data operations, and modern safety devices, we have adapted exercises that provide opportunities for students with experience on modern analytical equipment. The experience has increased student understanding of mineralogy and petrology with this more thorough treatment of X-ray crystallography throughout the geology curriculum and provides advanced undergraduate students with greater research opportunities. A one-hour companion course for Mineralogy (GEOL 241) implements substantive use of the revitalized XRD. Interdisciplinary student teams composed of geology majors, education majors, and environmental science majors work through exercises that are adapted from those developed with NSF support (CSI-8750682, USE-9151040, USE-9151549, USE-9251951) by faculty at Alfred University, Carleton College, Indiana University-Purdue University, and Smith College. This provides students with experience in simple phase identification, determining relations between lattice dimensions and crystal chemistry, unit-cell refinement, and characterization of clay minerals. Student use of the XRD in Petrology (GEOL 242), Sedimentary Rocks and Stratigraphy (GEOL 303), Senior Seminar (GEOL 490), and Geologic Field Experience (GEOL 496) has promoted an appreciation of the instrument as a research tool. This project has improved pre-college teachers' content knowledge of minerals and rocks as well as their pedagogical skills. The interdisciplinary approach has ensured interaction between students with different backgrounds and exposed them to the problem-solving approaches used in the sciences.