Scoring Qualitative Inorganic Unknowns at the Stockroom Sometimes one takes for granted the routines that are developed to facilitate instruction. We have been taking far granted a computer-managed routine for the random assignment and coded distribution of unknowns. We teach a qualitative analysis laboratory in which as many as 800 students each report on 14 unknowns during one semester. The computer programs randomly assign unknowns to each student, prepare charts to guide the rapid filling of the unknown tubes, and print decoding tables for easy scoring of student's reports. The entire process is handled by stockroom personnel. While the logistics of laboratory operation is a traditional stockroom function, the grading of student reports is not. Students complete their summary report on perforated 3 X 5-in. cards, and bring these to the stockroom window to be graded. The stockroom is provided with a computer-generated master unknown decoder arranged by section and student. The students wait in line with other "customers." Waits almost never exceed three minutes, and usually are less than 30 s. Both halves of the card are stamped "yes" or "no," and scored based upon the student's results. One half of the card is immediately returned to the student, and the other is filed in a partitioned box (a 150-ml beaker shipping box) for TAs to pick up after the lab period. The following outcomes result from this straightforward procedure. Students welcome the immediate feedback. TAs remain blind with respect to the composition of their student's unknowns and must respond to student questions as chemists rather than as answer keys. There is no overburden on the stockroom staff, even when 150 students are simultaneously meeting lab. The svstem is much less costlv than a camouter feedback svstem (where students fill out cards for delaved hatch n r o ~
time, a comprehensive record of student performance and progress. Since we use an entire semester of qual, this trivial management procedure has many, many cost benefits. We are sharing it with readers because so many visitors have commented upon our approach, one to which we have paid little attention since we started i t six years am. We will be deliehted t o share our Droerams with readers. but the" are written in APL. a
David W. Brooks, Thomas J. Tipton, and Darrell A. Kinnan University of Nebraska-Lincoln Lincoln, NB68588
Volume 60
Number 5
May 1983
389
