The project engages students in learning through the use of writing groups, in which small groups of students work together throughout the course to: 1) develop their oral and written communication skills; 2) incorporate small-group experiences into large courses; and 3) expand the students' understanding of the nature and methods of geology. Innovative writing assignments and associated small group activities supplement lectures in Physical and Historical Geology courses. The writing assignments develop observational and critical-thinking skills, introduce students to the practice of geology today, and foster awareness of the role of geology in society. As students meet to review each others' papers, they develop their oral and written communication skills, learn to use technical language precisely, discuss interpretations, and evaluate arguments. Teaching assistants, trained undergraduate geology majors, monitor the group work, respond to and evaluate the short papers and participate in small-group activities.