RESOLVING THE BREADTH VERSUS DEPTH VERSUS INQUIRY DILEMMA IN INTRODUCTORY COLLEGE GEOLOGY COURSES

Instructors of introductory geology courses, especially those with large classes, constantly face the dilemma of how to balance the coverage of diverse topics versus an in-depth treatment of key concepts or spending time helping students do scientific inquiry. As part of a class-redesign effort, we developed a suite of approaches and assessment tools that allow us to simultaneously address these three competing aspects of breadth, depth, and inquiry. The class is a semester-long course with ~220 students, nearly all nonmajors. At the start of the semester, students receive a What-to-Know (WTK) List in which each item is linked with a two-page spread in the textbook. Students are then responsible for each item, and know they are responsible even if that subject is not covered in lecture. Freed from the necessity to cover every topic, we devote much class time to having students observe, interpret, and discuss geology. To demonstrate their breadth of knowledge, students take weekly, online multiple-choice quizzes derived from items on the WTK List. To assess deep knowledge, there are four exams, during which students construct two fully developed concept sketches. For each exam, the instructor selects the two concept-sketch questions from 9 to 12 possible questions provided to students along with the WTK list. During each exam, we pass out blank sheets of paper and then display two concept-sketch questions on an overhead. Students draw and explain each concept sketch on one side of the paper. Some advantages of this style of exam are that (1) students ideally develop complete answers — and therefore deep knowledge — for each of the 9 to 12 possible concept-sketch items, (2) it is difficult for students to bluff their way through a concept-sketch exam, and (3) there are no photocopying costs. To assess inquiry skills, students complete each of the chapter-ending Investigations from the textbook, either online or on paper worksheets done in class and in small groups. Using this overall three-pronged approach, students are exposed to and assessed on a broad range of topics, but also need to have in-depth knowledge of about 40 topics. The decoupling of multiple-choice items from concept-sketch questions resulted in significant improvement in the quality of concept sketches and in student fluency with geologic concepts and language.