Teacher Demonstrations: The Effect on Student Task Involvement Warren Beasley Department of Education, University of Queensland, Brisbane, Australia 4067
The generation of curricula developed during the 1970's rewired a transformation of interaction patterns in science cla&ooms (1). These materials have employed a more heuristic approach in which pupils are encouraged to stop, think, and suggest modifications or further experiments. The emphasis on student-centered laboratory activity tended to reduce the role of teacher demonstrations. However, many teachers came to the view that open-ended experiments were very time-consuming and often an inefficient practice for teaching or illustrating routine subject matter (2). This has resulted in many science teachers employing more teachercentered activities. A trend back to a more teacher-centered approach to .. learning in high school classrooms has heen continuing since thc late 1970's (3).In this light, the role of the demonstration becomes crucial to the contkued motivation and enjoyment by students of high school science. The empirical findings reported in this paper substantiate the proposed effects that demonstrations have on improving student attention and involvement in the class. Methodology All observations were made in a regular science classroom setting. The sample of teachers and their pupils came from 24 science classrooms in six Brisbane high schools. There were three Grade 8 classes, twelve Grade 9 classes and nine Grade 10 classes with a median class size of 27 (range 20-36). Sixteen men and eight women teachers volunteered to participate in the study after the project was descrihed a t meetings of the science teachers in each school. It was planned that each teacher would he ohserved giving four science lessons, each about a month apart. The four lessons which were observed represented the teaching patterns which would normally occur at that time. Demonstrations were undertaken by nine teachers over the four occasions. Of the intended 96 lessons. 91 were recorded. Each lesson was recorded on two videotapes. One tape was made by a mobile camera with a zoom lens that tracked the teacher from a position a t the hack of the classroom (Teacher Tape). The other tape was derived from a fixed camera with a wide-angle lens, in a corner at the front of the room facing the pupils (Pupil Tape). The teacher wore a cordless radio microphone, and two omnidirectional microphones on f l w r stands were placed among the pupils. The total input from these three radio sources constituted the soundtrack on the video tapes. Observing- Pupil . Behavior The 91 pupil tapes were coded for pupil task involvement (4,51.The categories for task involvement aregiven in Figure 1. The pupil hehaviors were defined in the following way. 1) Definitely in the assigned work, task, or expected behavior
mode. To he coded as "definitely in," the pupil has to exhibit overt signs that he is "in" the prescribed activity. 2) Probably in the assigned work, task, or expected behavior mode. For the hehavior to be coded in this category,the pupil must he (1)in aposture from which it can he reasonably inferred that
I
"mnnitely in
e
I
~ in" t b TO*
w
marn9k"
~
I
y "waiting ' for 4 b f t n ~ sm s~k t me r0.k
Task
Figure 1. Pupil task involvement categories used to code the behavior of pupil in science lessons.
he is "in" the res scribed activity, (2) not actually writing or otherwise showing clear signs of being "in." 3) Waiting after completion of the assigned task. To be coded as waiting the pupil must have exhibited that he has completed a set task, and the investigatorjudges that he has nothing more to do hut wait until the teacher allocates another task. The pupil must manifest a "waiting" behavior, e.g., sitting quietly, fiddling with pen, staring around. 4) Out of the assigned work, task, or expected behavior mode. This is coded when the pupil shows no actual or postural signs of being "in" or shows clear signs that he is "out"of the prescribed activity. For example, the pupil might he doing something other than the designated task, daydreaming, or fiddling with an object on the desk or bench; he might he generally inattentive to a task or engaged in deviant behavior. Six pupils were selected for observation from the videotape (Pupil Tape). The pupils were selected such that equal representation from all regions of the room was assured and such that pupils were not in close physical proximity to each other. The hehavior of these pupils was coded by six trained coders whose observer agreement coefficients h a d a mean of 0.72 (5). Each of the six ~ u ~ iwas l s coded continuouslv throu~hout the observed lesson. ' The reliahilitv ( 6 ) with which task involvement was ohsewed in the 24 & & o m s was determined by calculating the intraclass correlation coefficient (7). The reliabilities of the mean task involvement scores for four observations in each classroom ranged from 0.63 ("probably in") to 0.82 ("waiting"). These high values indicate that the levels of task involvement in the 24 classrooms were ohsewed to he reasonably stable across four observations (5). Finally, the 91 lessons were coded into distinct lesson segments. These segments of lessons were defmed as time periods of variable length which were characterized by distinct comnlementarv sets of teacher/ounil behaviors. A descri~tionof these segments is presentediithe table. I t is the exposition, exnosition with nrons. and demonstration seements that are being addressed in'this paper. This divisionof lessons into distinct seements was essential. I t has been armed that the "whole lesion" is an adequate unit on which tocalculate the means of teacher behavior categories (8,9). Results The mean values of the pupil task involvement scores for the exposition, exposition with props, and demonstration lesson segments are displayed in Figure 2. Comparison of the Volume 59
Number 9
September 1982
789
Kay Exp =
Twhsr Exposltlon Exp/P= Temher Exposition with a Pmp Den-m = Ternher Demomtmtlon
Teacher Exposition
Teacher Demonstrafion
Figure 3. Class task involvement for teacher exposition and teachar demonstration lesson segments.
Figure 2. Student task involvement levels for each lesson segment.
means of pupil task involvement in each of the settings is difficult since all teachers did not use the three settings (exposition, exposition with props, and demonstration) over the four observational periods. By using a t-test for paired samples, comparisons of the effect of these teaching segmentswere possible. The nine teachers who undertook demonstrations obtained a significantly higher student task involvement than they did during exposition segments with the same pupils ( p < 0.05). However, no significant improvement in pupil task involvement occurred when expository teaching was supplemented by a prop. The means of each of the segments are displayed in Figure 3. Those teachers who undertook exposition and demonstration modes of teaching are shown with an X. The improvement in task involvement is clearly evident. Discussion The trend away from lahoratory-centered teaching in high school science courses has been evident for a numher of years. The role of the teacher demonstration in science classes must not be allowed to suffer the same fate. The findings presented in this . naner . have indicated that onlv nine of the twentv-four teachers in this study were observed using class demonstration methods. 1Iowever the significant aspect of these rlawrooms were the inrrraard ic,~wliof iou~ilnrt~ntionand task inuoluement during dernonstra& iesson segments. Expository methods were much more common, hut in the eyes of the pupils, teachers perform hest when they are conductingthe classroom demonstration. Literature Cited (1) Power, C. N.. "A Critical Review of seienee C1sasroornlnteteetionStudies."Studies inSei. Edlr., 1.1 (1971). (2) Aruodel, D. P.."An Evaluation ofthe ConceptualSchemesApproachto Science Currieulurn Development," J. Re$. Sci. Teoeh., 3,255 (1965). (3) Tulip, D., "Surveyof SeienceCurrieulvmMaterials 4 in Y e m MOin Queensland in 1980," The QuemdondSei Teaeh.,3. l(1980). (4) Kounin, J.. '"Disciplineaod Gmup Maowement of Claasmorns," Holt, Rimhart and Winaton, NawYork, 1910. (5) Butler. J. E., Beasley, W. F., Bucklcy. D. andEndsan, L.,"PupilTasklnvolvunent in Science Clapsrwms," Rea. Sei. Edue., 10.93 (1980). (6) Medley, D. M.. and Mitzel, H.E., "Meaaurinp Clmmm Behsviour by SyMrnatle Observation," in Gage. N. L. ~Edifor),"HendbmkofR~aearchoonTeaehing~ Rand McNally, Chicego, 1963.
790
Journal of Chemical Education
Segments of Lessons Type
Function
Organization
To prepare students for the implementation of a learning activity that forms the next segment. Exposition (no To present new material which props) (EXP) contributes to the cognitive or skill aim of lhe lesson, by means of "Teacher Talk." E~position TO present new material which (with props) contributes to the cognitive or (EXPIP) skill aim of the lesson by means of "Teacher Talk." Demonstvation To present or iilusmta new (DEMO) material by means of a teacherpresented activity which develops in format over a period of time. Small Group TO present or illstrate new Activity material which contributes to the cognitive or skill aim of the (SGA) lesson. Individual To present, illusbate, or give Activitv llAl. Oractice at new material which conlriouteo to the cognitive or 6k I aim of m e lesson TO present students with information via notes on lhe board (wrinen in silence) or by verbal dictation. Testing (TEST) To assess student understanding of previously learned material through prepared test instruments.
..
.
Pupil Task Srmcture Perform requested activlly.
Listen Watch Answer Questions Write notes. Listen Watch Teacher Answer Ouestians Write Watch prop. Listen Watch Teacher Answer Questions Watch Demonsbation Write. Manipulate apparatus Take notes, collate data.
Read Solve Problems Summarue rnater a1 Wme notes, listen
Write answers
(7) Rowley, G.L.. '"TheReLiabiiihr of Observational Mcasuns." A m . Edw. Roa. J. 13. 15 (1976). (8)MffiaaiB., Wardrop, J. L.andBmdqM.A."ClaasmomObswationSehern~a: Where Arethe Ermra?.Amer. Edue. Ree. J., 9.13 11972). (9) Medley, D. M.."The EffeetivenessofTeachers," in Psterson.P. L and Walberg, H.J. (Editors),'"RBssarchan Teachin6. Coneeptr. Fimdinga and Irn~Lieatiti~,'' MeCutehan, Berkeley, 1979.
