Paul G. Rasmussen Raymond L. H O U and Robert B. Kozma The University of Michigan Ann Arbor, M I 48109
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A One-Term Stand Alone General Chemistry Laboratory Course
With aid from the Exxon Education Foundation and Universitv course development funds, we have dismantled a very traditional and even jaded general chemistry laboratory course offering down to its hare hones, and rebuilt it with an overall design t h a t incorporates the various technological aids that our sponson were prepared to support. Such a comprehensive approach also depended on the cooperation of our colleagues both inside and outside the chemistry department. Our formal objectives were fivefold (see Table 1). T o accomplish all of these in substantial measure in any course would he a challenpe, but especially in a course as traditional, formal, and struciured as freshman lab. In facing this challenpe, we looked a t previous efforts and decided that a "hand-aid" annrnach would not do. We develooed a comprehensive plan by studying the course logistics, by analyzing the learnine~.nrocess involved. and bv reviewine all of the available teaching tools. The plan was realized through a variety of teaching strategies-some quite traditional, some very new. Our approach to cost-cutting was largely through reconsideration of course design and logistics. These aspects may he boring to the nonspecialist, but experienced instructors know how tightly they constrain what iipossihle. Equipment, supplies, lab stations, hoods, stockrooms and schedules are all vital narts of a lab ooeration. We made a number of chanees in the old program which are summarized inTables 3 and 4. We heean bv, senaratine the lab course from the lecture. . thot~:h .;tudents must eventually take lanth \\'? (loutiled the Itmrth d the lab oeriuds t n m 2 to I hr includinr: a shorr poG-lab recitation,and halved the number of lab periods from once weekly for two terms, to once weekly for one term. This system offers major scheduling advantages, and indirectly, lower costs. It makes more efficient use of an 8-hr day. It permits more freedom for student elections. Weaker students are obliged to take a lecture term prior to electing lab. The lecture .drop-outs do not preempt a relatively scarcer lab place. The fewer, longer periods devote proportionately less time to checking in and out. The flexibility that this system brings is not without costs. The lahoratorv manual must now carry the burden of pro\,iding adequate backgrot~ndtu the student without becoming encvcl(~lied~c in scope and "cookbook" in 3pproa~:h.Wt' have written new lab manual, which has a number of learning aids within it. These aids were built in after the formative evaluation showed that "structure" in the written materials was a factur of cignitirant strength as a learning aid. By structure we mean: hiplrl~#hting(tric~lfitdditimaltype fares),self t r s h practice prr.hlrnis, m.tlinec, and o\,err statements of objt,rIII:PY.The lab manual was redrafted twice durinr the course of the project and we believe it can now support'the "standalone" lab course without an accompanying textbook. We also looked hard a t the old program from the standpoint of organization and noted several defects. Because the periods for actual lab work had been only 2 hr long, a high proportion of the time was consumed setting up and putting away eauioment. A few minutes delav, for anv cause. was a potential d;saster with respect to finishing the experiment.- he lab periods were frenetic with activity and the students complained about being rushed. The supposed reinforcement of lab and lecture topics by coordinated treatment was frequently out of phase, such that students were not prepared to handle the lab task a t the appropriate time. (It is our impression that many programs that claim to have a close lec~
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ture-lab relationship fail to achieve it in practice.) Although it seemed sensible logistically to have a pre-lab recitation (a practice of many years standing), we observed that in fact, it was being used to tell the students what to do, how to do it, and what to see, and what it meant. The pre-lab recitation was gutting the lab as a first hand experience-students became accustomed to not reading the manual in advance! To attack these problems in our new course, the traditional pre-lab recitation was dropped and a shorter post-lab period added.
Table 1.
Objectives
Decrease Lab Expenditures: $/Student Increasing Learning: Equal or Better Achievement Increase Quality:Less Prescriptive More Experimental
Improve Aniiudes: Variety to Approach Widespread Use
Produce Materials Suitable for
Table 2.
Methodology
Cost Cuning: Course Redesign Learning Analysis: Motor skills and Experience with Real Stutf inductive Demonstration of Principles Deductive Systematics Chemicals end Apparatus Teaching TOOIS: New Lab Manual Videotapes Computer Simulations Table 3.
Courses
Term I
Term I1
Old'
113(4 CR) lec-lab weak bkgrnd 114 (4 CR) lec-lab strong bkgrnd
New:
123 (3 CR) lec weak bkgrnd
c 126 (3 CR) lec 125 (2 CR) lab
124 (3 CR) iec strong bkgrnd 125 (2 CR) lab
c 126 (3 CR) lec
a
7
Table 4.
Old:
New
116 (4 CR) lec-lab
Weekly Course Hours
Term 1
Term I1
3 hr lec 1 hr rec 1 hr pre-lab rec
3 hr lec 1 hr rec 1 hr pre-lab rec
7 hrlwk
7 hrlwk
3 hv lec 1 hr lec-rec 4 hrlwk
3 hr lec 1 hr lec-rec 4 hrlwk
3.5 hr lab 0.5 hr post-lab , 1 h lab-iec 5 hrlwk
Volume 57, Number 3, March 1980 / 191
In order t o replace sMnr of the instructiona~F I Q ~ hlit Q ~ ~ u.ith pre-lab recitation and the now +eoarated lecture, we added hack I hr wk uilerture to the I a h o r a t ~ n se8,11rse.T h c onre-a-week l p r f u r provides ~ a rent ral ftr.ui h r the c
