Effective and Efficient Use of Classroom Time Marcus E. Jorgensen' Department of Physical and Ocean Sciences, U. S. Coast Guard Academy, New London, CT 06320 Steiner, in a paper entitled "Encouraging Active Student Participation in the Learning Process" (I), stated that it is important "to develop ways to increase active student thinking in the lecture hall." Not only do I agree with this, but also I think that his ideas about class discussions and lecture demonstrations, as well as his innovative suggestion for small group problem sessions, can he expanded and extrapolated into a teaching philosophy which is concerned with hoth the effective and efficient use of each 50-minute time period al- lotted for "lecture." This paper will present a basis for such a philosophy and offer some practical suggestions for the freshman chemistry instructor with, optimally, class section of not more than 25 oeonle. At present, this &ching phdosophy, which has been con- tinually evolving, is hased on the follow~ng three premises 1) The attention span for the average freshman student, or anyone for that matter, is considerably less than 50 minutes. 2) Time is precious. 3) The instructor's primary role is not that of a disseminator of in- formation. It is obvious that we can think much faster than we can speak. Because of this, it is easy for a student's thoughts to wander from time to time. In fact, a study by Schoen (2) showed that, at anv one time, only 62% of college sophomores in a psychology rlass were thinking about what the lecturer was saying or demonstrating. Another study by Cameron and Giuntoli (3) found only 47T of a college class paying good at- tention to the lecturer at any one time. The second premise was stated very clearly by a professor I once had in class. He said that the greatest sin that any person can commit against another, short of murder, is to waste someone else's time (4). We all have only a finite amount of time and it is. therefore. verv valuable. Obviously, an instructoi h& to disseminate some infor- mation. But, the third premise says that this is not his or her primary role. More important than providing information is organizing it, explaining it, motivating students to learn it, and in general facilitating the learning process. This includes di- recting that process, i.e., providing learning goals or in some way letting <he studintiknow whit they areto learn. It then becomes their responsibility to accomplish those goals and the professor's respo&hility help them. Now. eiven the first premise, it does not make sense to lecture fir 50 minutes if students cannot listen for 50 minutes. Since onlv approximatelv one-half of the students are listening . .. at any one time anyvay, it certainly 1s not a very efficient use of our and our students' \,aluahlp time. Therefore, when I plan my class time, I try to minimize the amount of time that I lecture and maximize the time the students put their minds "in gear." I also try to make efficient use of the time by doing something for the student in class that the student could not do alone by reading the text. For example, I explain what I think might be confusing in the text or present the "big pic- ture" to k e e ~ the subiect matter in perspective, or I show an ~~ ~ . . occasional movie, give a demonstration, or start up a discus- sion. What I feel is mast effective, however, is problem solving. Schoen's study showed that at ky one time-83% of the st;- ' Current address: Training Division, US. Coast Guard Training Center, Petaluma. CA 94952. dents were attentive to the topic presented to them in a problem-solving session. Also, Silherman (5) lists, in rank order, suggesti&s for improvement of freshman chemistry courses; the first one on the list is "greater emphasis on problems in lecture." I spend a significant part of class time in problem solving. Sometimes, I divide the students into groups, and at other times, I have them work individually. I have the time to do this because of the application of the third premise. When I feel that the textbook or a handbook adequately covers some point, then I do not cover it in class or I will do so only briefly. Mv nrohlem sessions are less formal and much more fre- quent than what Steiner reported. My classes have approxi- mately 20 students of which few or none are chemistry majors and all of whom are taking General Chemistry as a required course. What I do most often with them is &ve them a problem to work and, while they work, I walk around the room giving hints only sparingly. When a student gets an answer he or she will raise his or her hand and I walk by and say "yes" or "no." When they have the wrong answer, they often want me to find their mistake, but I refrain from doing that and tell them to check their work. I do not let students get toofrustrated, hut I feel that if they can find their own mistake, they are less likelv to make that mistake again. When about one-half of the c~asH has the right answeri Stell them all to make sure the person next to them can do the problem. During this time, I can give individual help for the few that are really having trouble. Not only do they get individual help, but also the others get assisthce from thcir classmates who in some cases may he betcer able to explain a conrept on a student's level. Furthermore, any student who explains the solution to a problem gets additional reinforcement as he or she tearhes someone else. It may take me 10 minuws to do a problem this way that may otherwise have taken five minutes if l had done the oroblem on the hoard for the rlass: hnwever, I think it is time well spent. At the end of the 1981 Fall Term W. J. McKeachie's, "Student Opinion of Teaching and Course" evaluation form was used. The total responses from three class sections, one of Chemistry I1 and twobf chemistry I, to the question, "Does he stimulate thinking?" were as follows. Dull 0 0 7 22 24 Stimulating The responses from only the Chemistry I1 section which was made un of those who had ~reviouslv failed either Chemistrv I or Chemistry I1 were ' Dull 0 0 1 6 8 Stimulating Although, I do not know what the results would have been if I had used a more traditional approach, I feel that I was successful in stimulating thought in most of the students in Chemistry 1and I1 and thus used the class time effectively and et't'iriently. A suggested area of future research mould he the comparison of traditional lecturr classes with classes em- phasizing active student participation. Lllerature Clted (1) Steincr.R P., J. CmM. EDuC., 51.433 (1980). (2) Schoen, J.R.. J. ofEd.Reseoreh.63,387 (1970). (3) Cameron, P., and GiunDI, D.,Infollerl, 101,63 (19721 (4) Pmf. J. A. Santini, Connecticut College. (5) Silbermao,R.G., J.CHEM.EDUC..58.1036 (19811. Volume 61 Number 6 June 1984 523