MCT: An alternative in high school chemistry - Journal of Chemical

Results of a pilot study of "Modern Chemical Technology," a two-year junior-college program designed to train chemical technicians...
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Patricia S. O'Sullivan Curriculum Research and Development Group and Robert L. Pecsok University of Hawaii Honolulu. 96622

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MCT: An Alternative in High School Chemistry

Chemistry curricula introduced in the last 20 years have been characterized by their response to technical and social changes in the American culture. The post-Sputnik programs were intended to compensate for a deficiency in technical personnel in the United States. New programs of the 70's reflect the more social concerns of the American public, often emphasizing environmental and consumer chemistry. However, we should ask how well these curricula responded to student needs. The post-Sputnik programs were praised for their emphasis on broad chemical concepts versus large numbers of diverse chemical facts. Science was presented as an on-going and changing activity in these programs. The laboratories stressed an inquiry base.' However, from the literature and from teacher comments, these strengths of the programs were significantly undermined by some serious weaknesses. The weaknesses represent a failure to teach what the student m sophisticated, needed. The programs were characterized as t too much oriented toward the potential scientist. They simply were not for the average student. The authors had paid little attention to the psychology of learning.' Dissatisfaction with the post-Sputnik programs and changing emphasis on science in the society has brought forth a new burst of chemistry curricula. The chemistry materials that appeared in the early 70's have an orientation toward the application of chemistry in such areas as biochemistry, nuclear chemistry, organic chemistry, and environmental chemistry. These areas reflect the chemistry present in our everyday life rather than the concepts behind the chemistry. In addition, there has been an apparent shift from the knowing a few concepts well of the 60's to the experiencing a larger number of concepts generally of the 70's. Have these new chemistry programs responded to student needs as well as they have responded to the needs of the society? How can we judge whether materials are suitahle for particular students? To answer this we can turn to psychology and particularly to Piaget. Major direction comes from Piagetian studies that have been conducted on high schwl students. The majority of high school students do not demonstrate formal operational reasoning, especially with regard to understanding ahstract science subject matter. A recent review of the Piagetian studies relating intellectual development to science achievement in adolescents supports the contention that the majority of high school students function a t the concrete operational stage of intellectual development.

Yet, without a doubt most high school chemistry programs are written at the formal leveL2 'I'o meet the needz of many high srhool students it appears that the chemistry materials should he concrete in orientation. A concrete nroeram is characterized bv first-hand exoeriences. The students make inferences, organize information, make observations, make identifications. On the other hand, a program which is formal in orientation involves the student's and theoretical tvnes deductive.. Kvoothetical. .. .. of reasonine." The formal chemistry materials tend to he symbolic and mathematical. At the University of Hawaii, University Laboratory School (ULS) we attempted to find a chemistry program written at the concrete operational level. As well, we desired to present to these students an orientation toward chemistry that would make them aware of possible future employment in a science field. We thought that a technically, and therefore concretely, oriented chemistry course might appeal to students previously alienated by the ahstract and theoretical approach of many high school chemistry courses. The sciencedepartment at ULS was also concerned that the program be appropriately challeneine ,. .. for these students oneratine a t a concrete stage oi intellrct~~nl development. \Valered-down nhstrart rhemistrv would not t~esuitnhlr.Currirula of the 70'snerr renemllv not considered suitable since the multiconcept approach was eeuerallv believed to be fairlv ahstract. - With these criteria in mini ULS chose to do a pilot study of Modern Chemical Technology (MCT).WCT is a two-year junior college program designed to train chemical technicians. In MCT concepts are develo~edthrouah first-hand laboratow experiences with an emphasis on deieloping the skills and understanding necessaw for a technician. The question ULS a ished to answer was: \ ~ o u l dhlCT as written f(;r terhnicians he appropriate and useful 11,high school students'? Beforeexploring the results i f the pilot study, i t might be instructive to review some of the characteristics of MCT. As

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Collette. A. T., "Science Teaching in the Secondary School,"Allyn and Bacon, Boston, 1973, p. 124. Chiapetta, E. L., Science Education, 60,253 (1976). :'Far further discussion of MCT, see: Peesak, R. L., J. CHEM. EDUC., 50,823 (1973); Pecsok, R. L., Journal of College Science Teaching, I (2),31 (1971); Chapman, K., EngineeringEdueotion, 62,

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835 (1972).

' Herron, J. D., J. CHEM. EDUC., 52,146 (1975).

Volume 54. Number 1, January 1977 / 43

a junior college program, MCT is oriented toward serious chemical education for these students. MCT is directed toward students with average high school records-students who are mechanically minded rather than academically oriented: thus the readine level in MCT would probablv he very suitable for high scho:l students. T o allow for learning from first-hand lab experiences, MCT experiments are integrated into the text. Information on skills is developed right in the lab itself. The freauent use of common chemicals makes the lab experience easier to remember. There is not a strong mathematical emphasis as would he found in a more formal text, hut the mathematics are introduced as needed. Topics are not isolated bv chapters, but are developed continually through the text. Insrr~mentltionis emphasized as would he exoerted fl~ra rourse fur rechnicians. I.abs, instrumentatiun, and narrative are tied together by several themes which interest chemists such as purity and identification of samples. Is MCT really written a t the concrete level? The above paragraph certainly suggests this conclusion. Another guide might he Heron's article, "Piaget for Chemists" "In this article Heron includes a chart contrasting 15 competencies as they would he addressed for concrete and formal thinkers. Acids and hases described in terms of use of litmus paper would be suitable to an individual on the concrete operational level; acids and hases defined in terms of electron oair donors and acceptors would not he suitable. Asking a student to cofistruct a cooline curve and to describe the effects of an impurity would h;? reasonable; asking a student to explain why thk olateau occurs during the phase change would not be reaionable. The distinctions chat Heron makes are indeed reflected in MCT. The concepts are approached a s a person a t the concrete stage of intellectual development could handle d them. It could he asked if it is worth bothering with presenting the concepts a t the concrete level. First, there are many technical jobs which require good concrete operational development, hut are not so dependent on formal reasoning. Second, it has been asserted that by presenting the concepts of chemistry a t the concrete level an ultimate transition to formal thinking mieht be realized a t a later time.4 .\r University 1.al1oratory School 23 studenti were enrolled i n \1C"I'. An,,thrr 56 students wrrr cnrullcd :n a forn~allevel course. "Foundations of Chemist~.""I'he 23 students were either of low scientific ability or of high academic ability hut with low motivation or with low interest toward science. Seniors taking the course were able to elect MCT. Juniors fitting this description were randomly assigned to MCT and to a control class which used "Foundations of Chemistry." Under normal circumstances most of these students would not have enrolled in chemistry due to its reputatim as too diificulr. S m w of these studrnts in MC'I'did b~lievethat they might Iw interested in a technical or science related career. '1'0 undrrtake the .oroiert. . . few .ohvsical - adiustmenrs hnd 10 be made to the high school combination laboratory-classroom. The instructor did have to do a bit of leg work to find access to equipmenthnunded by the instrumentation sertion. 'l'he instructur was delighted t u discu\w that relarivelv iew sulutions or.unugual chemicals were required for MCT. The students often make and assemble their own apparatus and mix - their own solutions. The structure of the MCT classroom focused around the ~~~~~

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"Toon, E. R., and Ellis, G.L., "Foundations of Chemistry," Holt, Rinehart, Winston, Inc., New York, 1968.

44 / Journal of Chemical Education

laboratories. In the lab the student worked on his techniaue for taking melting points, freezing points, densities of'all ohases. usine the balance, titratine, etc. The pilot group did have the opportunity to use a gas chromatograph ion a-field trip), an analytical balance, a spectrophotometer, and a p H meter (borrowed). The skills necessary to use these instruments are taught in the lab. This experience gives the students a sense of control over what could be an abstract experiment. As a result of their experiments the MCT students later instructed others in the use and care of available instruments and in common techniques. The MCT student is made aware of the purpose of the labs. He is given responsibility in the lab. The laboratories supplying the real experience to the concrete thinker serve as the hase for discussion in the text. Along with the laboratories. MCT offers in the text a number of Applications and ~xercises,reflecting applications of the topics just discussed and practice in exercises pertinent to the particular topic. In the classes a t ULS, Applications and Exrrcisci twcame a tuol fur small gruup and peer teaching. What did the students enjuy ahour hlCTl (:enerally, they fwnd the reading mterestiny. They felt that thecourse was serious, not easy watered-down. The labs and Applications and Exercises were within their capabilities. The students enjoyed the manipulative and measurement aspects of most of the labs. It was rewarding to them to explain what they were doing in labs to other students. The use of instruments gave them both a feeling of expertise and an awareness of the role that instruments play in chemical analysis. Construction of apparatus as part of the lab did stimulate their interest. Overall, MCT did appear to be successful for these students. Before the pilot vear was completed an additional 16 students from the co&ol class had started to study MCT. An effort had been made to bring the more formal presentation of "Foundations in chemistry2' down to a concrete level. However, that effort was not realistic. Concrete activities represented an alternative presentation not a watered-down one. The student reaction toward MCT was favorable and the staff entertained the notion of continuine the course the next academic year. However, to viably use MET a t the high school level the instructor believed that some adiustments would have to he made. At ULS topics from the first three of the seven volumes were used. Some topics such as eauilibrium, oxidation-reduction, and kinetics which appear later than the third volume would have to be incorporated in earlier materials. The instructor must arrange for classes to visit local lahoratories to see, and hopefully use, instruments mentioned earlier, or invite to the class guest speakers who might bring instruments with them. This aspect of the course certainly appears as a timely opportunity to bring career awareness into the classroom-especially for science careers which might interest these particular students. Some reworking of the language in the text and of the laboratory procedures is ad; vocated for a high school edition. The net reaction is that although MCT was written for technicians, its emphasis is suitable for mauv. hieh .. school students. In ~.mcluswnMCT rppeilri I(, be a wahle chemistry course fw all students who arc at the cotmete ituee of intellectual development in science. Students who paiticipated in the MCT Droeram a t Universitv Laboratorv School were found . .. t o be mut~vntedtoward chrmistry m a manner not anticipated in other imwmni. .MC'I' was found 11, he an exritine. currirulum that has placed chemistry in a perspective we71 suited for many students in high school.