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Highlights ~~

SUSAN H. HIXSON National Science Foundation

Washington. DC 20550

Georgia State University Atlanta. GA 30303

Projects supported by the NSF Division of Undergraduate Education

Cooperative Chemistry Laboratories

Melanie M. Cooper Clemson University Clemson SC 29634

Ideally the general chemistry laboratory should interest the students, leave them with a positive image of chemis- try and science, and begin to teach the skills used by prac- ticing scientists. Students learn such skills as pmblem- solving, data evaluation and interpretation, experimental design and implementation, and critical thinking. Unfor- tunately, as the National Science Board ( I ) reported, labo- ratory instruction "has deteriorated to the point where it is often uninspired, tedious and dull". I t is little wonder then that many students fmd chemistry irrelevant and boring.

We are developing a new laboratory format for general chemistry that exposes students to the process of scientific problem solving, emphasizes collaborative work, and re- quires the students to communicate their results both orally and in writing.

During the first laboratory period students are assigned to groups of four. The groups are as heterogeneous as pos- sible with regard to gender, race, and age. Short coopera- tive learning exercises to build group identity are per- formed the first period. Over the semester, the groups work on three multistep, open-ended projects rather than one-lab-period, closed exercises. In the f r s t project, for ex- ample, the students are told that they are research chem- ists working for the EPA. A compound has been found in a landfill, and the gmup assignment is to determine its prop- erties, identify it, and devise and perform a synthesis. Each of the 5-6 groups in a lab section is given a different unknown compound.

Since a plan of action specific to the compound must be developed not all groups perform the same activity at the same time, though they will have to make use of the same experimental techniques. Our students devise and control their own experiments with assistance from teaching as- sistants rather than blindly following instructions from a lab manual. For the synthesis they choose the reaction, calculate how much of each reactant is needed, and decide on reaction conditions.

Besides the lab manual descriptions of laboratory tech- niques, instrument operation, and safety procedures, the students also have access to a computer program, Super- ChemLab, designed for our laboratories. This multimedia, HyperCard-based program contains audio, video and text clips illustrating laboratory techniques and their uses. If the students need to learn how to perform a titration, for example, they can access the video and text by choosing titration from the index. Because beginning students may not know if or when to perform a titration, the program also will pose a series of questions whose answers will lead the students to conclude that a titration would vield useful information. In thc new labs, ytudcnts lcarn ~ ~ ~ e r i r n c n ~ n l terhniques in the context of the experiment they have de-

signed; therefore they see the need for, and uses of, these techniques.

Most practitioners of woperative learning agree that the grade a student receives should reflect the individual ef- fort and achievement of the students (2,3). Consequently, only 30% ofthe total laboratory grade is a group grade. The rest of the grade comes from individual written reports, peer evaluation, and evaluation of lab technique by the in- structor. As a result, conscientious students will not feel that their grade is compromised by the make-up of the group, and the less enthusiastic student will not be as tempted to sit back and benefit from the work of his peers.

With total enrollments of up to 2,000 students per se- mester. wneral chemistrv laboratories are usuallv taught . .. hy pnriiate tearhinfi assktants. Careful attention is given to the rrainina and dcvclopmcnt ofTA's since their role is quite different from that in a traditional lab. They assume the role of an advisor and coach rather than that of the teacher expert. The TA's attend a workshop on cooperative learning and then meet weekly to discuss the progress of the labs. Commonly, the TA's are uncomfortable with their new roles at first; however, with training they adjust as the semester progresses.

In order to evaluate the success of our new labs we arbi- trarily assigned half the students to cooperative labs and half to traditional labs. Surveys of the students indicate that those in the cooperative laboratory settings are more positive about the experience and believe they learn more. Student performance in the lecture part of the course was also monitored. Since all students take the same lecture exams, it was possible to see if any correlation existed be- tween lecture performance and type of laboratory. Analysis of lecture erades bv eender reveals that the female stu- - " - dents in cooperative laboratories outperform their female Deers in the reeular laboratories bv 2 to as much as 10%. A - similar correlation was not found for males.

An analysis of drop rates also revealed a gender differ- ence. Male students dropped the course at a rate of 9% re- gardless of lab type. The drop rate for females was 13% for coop labs and 21% for regular labs. We are further investi- gating this apparent gender difference, since these results seem to indicate that cooperative learning may be a viable strategy for encouraging more female participation in chemistry.

Acknowledgement The author would like to acknowledee the followine

funding agencies for support of this proj& Thc ~ntional Science Foundation, Award #DUE 9155954 and the Fund for the Improvement of Post Sewndary Education, Award # P116B200009-92A

Literature Cited 1. National Snenee Board. Undergrndaot~Sciencp, Molh~moticsondEwimeri"gEdu-

c a t b x U S . Government Printing ORlce: Washington. DC, 1986. 2. Johnsrm. D. W.; Johnaon, R. T hrvnlng Together end Alone; Coopemtiw, competi-

hue, and Indiuidualistir homing: Holt, Reinhardt and Winston: New York, 1981. 3. Cooper, J.;Presmtt. S.: Cmk. L.: Smith. L. CmpemiivaIaarning ondColkgeInstruc-

fion;California State Uniwrsiv Founddim Long Beach, CA, 1990.

Volume 71 Number 4 April 1994 307