Concrete Materials and Teaching for Mathematical Understanding Author(s): Patrick W. Thompson and Diana Lambdin Source: The Arithmetic Teacher , MAY 1994, Vol. 41, No. 9 (MAY 1994), pp. 556-558 Published by: National Council of Teachers of Mathematics Stable URL: https://www.jstor.org/stable/41196106 REFERENCES Linked references are available on JSTOR for this article: https://www.jstor.org/stable/41196106?seq=1&cid=pdfreference#references_tab_contents You may need to log in to JSTOR to access the linked references. JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org. Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at https://about.jstor.org/terms National Council of Teachers of Mathematics is collaborating with JSTOR to digitize, preserve and extend access to The Arithmetic Teacher This content downloaded from 110.144.70.46 on Mon, 15 Feb 2021 10:40:56 UTC All use subject to https://about.jstor.org/terms RESEARCH INTO PRACTICE Concrete Materials and Teaching for Mathematical Understanding students to understand?" Too often it is Learning without thought is labor lost. - Confucius ers would not necessarily benefit from them. "What shall I have my students learn toHowever, Suydam and Higgins (1977) re- do?" If we can answer only the second ported a pattern of beneficial results for all question, then we have not given sufficient learners. Middle and upper primary stu- An experience is not a true experience until it is reflective. thought to what we hope to achieve by dents a observed by Labinowicz (1985) ex- - John Dewey particular segment of instruction or use perienced of considerable difficulties making concrete materials. sense of base-ten blocks, although Fuson we find common agreement that and Briars ( 1 990) reported astounding suc- effective mathematics instruction in cess in the use of the same materials in the elementary grades incorporates liberal teaching addition and subtraction algo- use of concrete materials. Articles in the rithms. Thompson (1992) and Resnick and Omanson (1987) reported that using base- Arithmetic Teacher no longer exhort us to use concrete materials, nor does the Professional Standardsfor Teaching Math- ematics (NCTM 1991) include a standard How shall we ten blocks had little effect on upper- think about this on the use of concrete materials. The use of primary students' understanding or use of their already memorized whole-number addition and subtraction algorithms, whereas Wearne and Hiebert (1988) reported consistent success in the use of problem? concrete materials seems to be assumed unquestioningly. concrete materials to aid students' under- My aim in this article is to reflect on the role of concrete materials in teaching for mathematical understanding - not to arResearch gue against their use but instead to argue Concrete for using them more judiciously and reflec- standing of decimal fractions and decimal numeration (see also Hiebert, Wearne, and on the Use of Materials Taber [1991]). These apparent contradictions are prob- tively. Our primary question should alably due to aspects of instruction and stuThe use of concrete materials has always ways be "What, in principle, do I want my dents' engagement to which studies did not been intuitively appealing. The editors of a attend. Evidently, just using concrete ma- turn-of-the-century methods textbook terials is not enough to guarantee success. Prepared by Patrick W. Thompson stated, "Examples in the concrete are better ban uiego ótate university for the student at this stage of his develop- We must look at the total instructional environment to understand effective use of San Diego, CA 92120 ment, as he can more readily comprehend these" (Beecher and Faxon 1918, 47, asconcrete materials - especially teachers' images of what they intend to teach and quoted in McKillip et al. 1978). Their apstudents' images of the activities in which pearance accelerated in the 1960s, at least Edited by Diana Lambdin Indiana University Bloomington, IN 47405-1006 are asked to engage. Patrick Thompson teaches at San Diego State Uni- in the United States, with the publication they of versity, San Diego, CA 92120. He is codirectorofthe Quantitative Reasoning Project sponsored by the National Science Foundation. theoretical justifications for their use by ^^nilil^^H Zolton Dienes ( 1 960) and by Jerome Bruner (1961). Preparation of this paper was supported by NationalA number of studies on the effectiveness Science Foundation (NSF) grants no. MDR 89-503 1of 1 What does this collection using concrete materials have been con- illustrate? and 90-96275 and by a grant of equipment from ducted since Dienes' s and Bruner' s publiApple Computer, Inc., Office of External Research. cations, and the results are mixed. Fennema Any conclusions or recommendations stated here are (1972) argued for their use with beginning those of the author and do not necessarily reflect official positions of NSF or Apple Computer. learners while maintaining that older learn556 ARITHMETIC This content downloaded from 110.144.70.46 on Mon, 15 Feb 2021 10:40:56 UTC All use subject to https://about.jstor.org/terms • •too TEACHER Seeing Mathematical ined later in this article. correct interpretations of materials - Seeing mathematical ideas in concrete namely, the one we intend they have. In Ideas in Concrete materials can be challenging. The material actuality the opposite is meant. It should be Materials may be concrete, but the idea that students our instructional goal that students can are intended to see is not in the material. make, in principle, all interpretations of It is often thought, for example, that an The idea is in the way the teacher underfigure 1. actual wooden base-ten cube is more constands the material and understands his or A teacher needs to be aware of multiple her actions with it. Perhaps two examples interpretations of materials so as to hear hints of those that students actually make. sidering the physical characteristics of will ob- illustrate this point. A common approach to teaching fracWithout this awareness it is easy to prejects, this statement certainly seems true. tions is to have students consider a collecsume that students see what we intend they But to students who are still constructing see, and communication between teacher tion of objects, some of which are distinct concepts of numeration, the "thousandness" crete to students than is a picture of a wooden base-ten cube. When one is con- of a wooden base-ten cube often is no more from the rest, as depicted in figure 1 . If aand student can break down when students concrete than the "thousandness" of a pic- student had a collection like that depicted see something other than what we prein figure 1# it would certainly be concrete. sume. tured cube (Labinowicz 1985). To underAlso, it is important that student stand the cube - either actual or pictured - But what might the collection illustrate to students? Three circles out of five? If so, create multiple interpretations of m as representing a numeral value of 1000, students need to create an image of a cube they see a part and a whole but not a als. They are empowered when they that entails its relations to its potential parts fraction. Three-fifths of one? Perhaps. But nize the multiplicity of viewpoints (e.g., that it can be made of 10 blocks each depending on how they think of the circles which valid interpretations can be having a value of 100, 100 blocks each and collections, they could also see three- for they are then alert to choose am having a value of 10, or 1000 blocks each fifths of five, five-thirds of one, or five- them for the most appropriate action tive to a current situation. However, having a value of 1 ). If their image of a cube thirds of three (see fig. 2). They could also see figure 1 as illustratteacher's responsibility to cultivate is simply as a big block named thousand, ing that 1 h- 3/5 = 1 2/3- that within 1 view. It probably will not happen if then no substantive difference accrues to whole is one three-fifths and two-thirds teacher is unaware of multiple inter students between a picture of a cube or an of another three-fifths, or that 5-^3 = tions or thinks that the ideas are "there" in actual cube - the issue of concreteness would be immaterial to their understand- 1 2/3 - that within 5 is one three and two- the materials. thirds of another three. Finally, they could Figure 1 is customarily offered by texting of base-ten numeration. This comment see figure 1 as illustrating 5/3 X 3/5 =1 books and by teachers to illustrate 3/5. is not to say that, to students, a substantive that five-thirds of (three-fifths of 1) is 1 . It difference never occurs between pictures is an error to think that a particular material and actual objects. Rather, it says only that concrete materials do not automaticallyor illustration, by itself, presents an idea unequivocally. Mathematics, like beauty, carry mathematical meaning for students. is in the eye of the beholder - and the eye A substantive difference can exist between how students experience actual materials and how they experience depictions of sees what the mind conceives. Teachers sometimes understand the dis- Period. In fact we rarely find textbooks or teachers discussing the difference between thinking of 3/5 as "three out of five" and thinking of it as "three one-fifths." How a student understands figure 1 in relation to the fraction 3/5 can have tremendous con- sequences. When students think of frac- materials, but the difference resides in how cussion of figure 1 and figure 2 as saying tions as "so many out of so many," they are they are used. This point will be reexam- that we need to take care that students form ^^■^^^^^^^^^^^^^^^^^^^^^^^^^^^H justified in being puzzled about fractions like 6/5. How do you take six things out of five? The second example continues the dis- cussion of fractions. Various ways to think about the circles and collections in It illustrates that how we think of the materials in a situation can figure 1. have implications for how we may think If we see • • • О О as one collection, then • is one-fifth of one, about our actions with them. so • • • is three-fifths of one. Suppose, in figure 3, that the top collection is an example of 3/5 and the bottom If we see 9 • • as one collection, then • is one-third of one, collection is an example of 3/4. Next com- so 0 ф # О О is five-thirds of one. bine the two collections. Does the com- If we see • as one circle, then • • • О Ois five circles, 3/5 + 3/4? Yes and no. If we were thinking bined collection produce an example of so # is one-fifth of five and • • • is three-fifths of five. If we see • as one circle, then Ф • • is three circles, so • is one-third of three and • • • О О is five-thirds of three. of 3/5 and 3/4 as ratios (so many out of every so many), then 3/5 + 3/4 = 6/9 (three out of every five combined with three out of every four gives six out of every nine, as when computing batting averages). If we understood 3/5 and 3/4 in figure 3 as frac- MAY1994 This content downloaded from 110.144.70.46 on Mon, 15 Feb 2021 10:40:56 UTC All use subject to https://about.jstor.org/terms 557 tions, then it doesn't make sense to talk about combining them. It would be like asking, "If we combine three-fifths of a large pizza and three-fourths of a small ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^H Three-fifths and three-fourths combined into one collection pizza, then how much of a pizza do we have?" How much of which kind of pizza? It only makes sense to combine amounts (|MO^) 3/5 <ř##5> 3/4 measured as fractions when both are measured in a common unit. Both answers (6/9 and "the question doesn't make sense") are correct - each in regard to a particular way of understanding the con- V crete material at the outset. Using Concrete Materials in Teaching Elizabeth H. "Models and Mathematics." SuchFennema, conve Arithmetic Teacher 1 8 (December 1972):635-40. and Hiebe Fuson, Karen C, and Diane J. Briars. "Using a Basephase of Ten Blocks Learning/Teaching Approach for First- It is not easy to use concrete materials well, and it is easy to misuse them. Several structing and Second-Grade Place- Value and Multidigit Addition and Subtraction." Journal for Research of thinkin studies suggest that concrete materials are convention 180-206. in Mathematics Education 21 (May 1990): likely to be misused when a teacher has in mind that students will learn to perform notation. Hiebert, James, Diana Wearne, and Susan Taber. we think about this? How can we think "Fourth Graders' Gradual Construction of Deci- mal Fractions during Instruction Using Different about this ? How shall we think about this?" some prescribed activity with them (Boyd 1992; Resnick and Omanson 1987; is also the heart of what Thompson et al. Thompson and Thompson 1994). This situ- ( 1 994) call "conceptually oriented" instrucation happens most often when teachers tion. use concrete materials to "model" a symSecond, concrete materials furnish somebolic procedure. For example, many teach- thing on which students can act. The pedaers use base-ten blocks to teach addition gogical goal is that they reflect on their and subtraction of whole numbers. Stu- actions in relation to the ideas the teacher has worked to establish and in relation to dents often want to begin working with the Physical Representations." Elementary School Journal 91 (March 1 99 1 ):32 1 -41 . Labinowicz, Edward. Learning from Children: New Beginnings for Teaching Numerical Thinking. Menlo Park, Calif.: Addison- Wesley Publishing Co., 1985. McKillip, William D., Thomas J. Cooney, Edward J. Davis, and James W. Wilson. Mathematics Instruction in the Elementary Grades. Morristown, N.J.: Silver Bürde« Co., 1978. National Council of Teachers of Mathematics. Pro- largest blocks, such as adding or subtractthe constraints of the tasks as they have fessional Standards for Teaching Mathematics. ing the thousands in two numbers. Teachconceived it. The discussion of figure 3 Reston, Va.: The Council, 1991. ers often say, "No, start with the smallest highlighted occasions where the teacher Resnick, Lauren, and Susan Omanson. "Learning to blocks, the ones. You have to go from right and the students might reflect on the to left." Would it be incorrect to start with the largest blocks? No, it would be uncon- fractional amounts for what it means to ventional but not incorrect. combine two collections. Since our primary question should be "What do I want my students to under- Understand Arithmetic." In Advances in Instruc- implications of various understandings of tional Psychology, vol. 3, edited by Robert Glaser, 41-95. Hillsdale, N.J.: Lawrence Erlbaum Associates, 1987. Suydam, Marilyn M., and John L. Higgins. ActivityBased Learning in Elementary School Mathematics: Recommendations from the Research. Columsuccessful bus, Ohio: ERIC/SMEE, 1977. Concrete materials can be an effective aid to students' thinking and to stand?" instead of "What do I want my teaching. But effectiveness is contingent students to do?" it is problematic when Thompson, Alba G., Randolph A. Philipp, Patrick on what one is trying to achieve. To draw W. Thompson, and Barbara A. Boyd. teachers have a prescribed activity in maximum benefit from students' use of "Calculational and Conceptual Orientations mind - a standard algorithm - and un- concrete materials, the teacher must con- in Teaching Mathematics." In Professional Development for Teachers of Mathematics, 1994 thinkingly reject creative problem solving tinually situate her or his actions with the Yearbook when it doesn't conform to convention or of the National Council of Teachers of question, "What do I want my students to Mathematics, edited by Douglas B. Aichele. prescription. In situations in which stu- understand?" dents' unconventional, but legitimate, actions are rejected by a teacher, students References Reston, Va.: The Council, 1994. Thompson, Patrick W. "Notations, Conventions, and Constraints: Contributions to Effective Uses of Concrete Materials in Elementary Mathematics." Journal for Research in Mathematics Education 23 (March 1992):123-47. learn once more that "to understand" means Beecher, W. J., and G. B. Faxon, eds. Practical to memorize a prescribed activity. Methods and Devices for Teachers. Dansville, N.Y.: F. W. Owens Publishing Co., 1918. Thompson, Patrick W., and Alba G. Thompson. Boyd, Barbara A. "The Relationship between Math"Talking about Rates Conceptually, Part I: A Concrete materials are used appropriately for two purposes. First they enable the teacher and the students to have ematics Subject Matter Knowledge and Instruction: A Case Study." Master's thesis, San Diego State University, 1992. grounded conversations about something "concrete." The nature of the talk should be (a) how to think about the materials and (b) the meanings of various actions with them. 558 Bruner, Jerome. The Process of Education. New York: Vintage Books, 1961. Dienes, Zoltan. Building Up Mathematics. London: Hutchinson Educational, 1960. ARITHMETIC This content downloaded from 110.144.70.46 on Mon, 15 Feb 2021 10:40:56 UTC All use subject to https://about.jstor.org/terms Teacher's Struggle. Journal for Research in Math- ematics Education 25 (May 1994):279-303. Wearne, Diana, and James Hiebert. "A Cognitive Approach to Meaningful Mathematics Instruction: Testing a Local Theory Using Decimal Numbers." Journal for Research in Mathematics Edu- cation 19 (November 1988):371- 84. Щ TEACHER