Curricular Treatments of Length Measurement in the United States: Do They Address Known Learning Challenges? John P

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Curricular Treatments of Length Measurement in the United States: Do They Address Known Learning Challenges? John P CORE Metadata, citation and similar papers at core.ac.uk Provided by UNL | Libraries University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Faculty Publications: Department of Teaching, Department of Teaching, Learning and Teacher Learning and Teacher Education Education 2013 Curricular Treatments of Length Measurement in the United States: Do They Address Known Learning Challenges? John P. Smith III Michigan State University, [email protected] Lorraine Males University of Nebraska‐Lincoln, [email protected] Leslie C. Dietiker Boston University KoSze Lee University of North Florida Aaron Mosier Michigan State University Follow this and additional works at: https://digitalcommons.unl.edu/teachlearnfacpub Part of the Curriculum and Instruction Commons, and the Teacher Education and Professional Development Commons Smith, John P. III; Males, Lorraine; Dietiker, Leslie C.; Lee, KoSze; and Mosier, Aaron, "Curricular Treatments of Length Measurement in the United States: Do They Address Known Learning Challenges?" (2013). Faculty Publications: Department of Teaching, Learning and Teacher Education. 330. https://digitalcommons.unl.edu/teachlearnfacpub/330 This Article is brought to you for free and open access by the Department of Teaching, Learning and Teacher Education at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Faculty Publications: Department of Teaching, Learning and Teacher Education by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. digitalcommons.unl.edu Curricular Treatments of Length Measurement in the United States: Do They Address Known Learning Challenges? John P. Smith III, Lorraine M. Males, Leslie C. Dietiker, KoSze Lee, and Aaron Mosier Michigan State University Lorraine M. Males is now at the Department of Teaching, Learning & Teacher Education, University of Nebraska–Lincoln. Leslie C. Dietiker is now at the School of Education, Boston University. KoSze Lee is now at the Department of Foundations and Secondary Education, University of North Florida. Corresponding author — John P. Smith III, Department of Counseling Educational Psychology and Special Education, 509C Erickson Hall, 620 Farm Lane, Michigan State University, East Lansing, MI 48824; email [email protected] Abstract Extensive research has shown that elementary students struggle to learn the ba- sic principles of length measurement. However, where patterns of errors have been documented, the origins of students’ difficulties have not been identified. This study investigated the hypothesis that written elementary mathematics curricula con- tribute to the problem of learning length measurement. We analyzed all instances of length measurement in three mathematics curricula (grades K–3) and found a shared focus on procedures. Attention to conceptual principles was limited overall and particularly for central ideas; conceptual principles were often presented after students were asked to use procedures that depended on them; and students often did not have direct access to conceptual principles. We also report five groupings of procedures that appeared sequentially in all three curricula, the conceptual princi- ples that underlie those procedures, and the conventional knowledge that receives substantial attention by grade 3. Published in Cognition and Instruction, 31:4 (2013), pp 388–433. doi 10.1080/07370008.2013.828728 Copyright © Taylor & Francis Group, LLC. Used by permission. 1 Smith et al. in Cognition and Instruction 31 (2013) 2 From the primary grades forward, many students in the United States, as well as in other countries (Bragg & Outhred, 2001; Hart, 1981; Nunes & Bryant, 1996), struggle to learn measurement. More than 30 years of empirical research, both large-scale studies and smaller more focused studies targeting student reasoning, have shown substantial weaknesses in students’ understanding of measurement. In the United States and other countries, children work in the elementary grades to measure many quantities, including time, weight/mass, capacity/volume, and temper- ature. But more attention is devoted to measuring space—length, area, and volume—than other quantities, starting in the first year of formal schooling.1 Despite frequent everyday experiences with spatial quanti- ties, many students do not understand units of measure, how the iter- ation of units produces spatial measures, or how commonly used tools (rulers and computational formulas) generate measures (Battista, 2003; Lehrer, 2003; Lehrer, Jenkins, & Osana, 1998; National Research Council, 2001, 2007). U.S. elementary students’ performance on the National As- sessment of Education Progress (NAEP) has been lower in measurement than in most other domains (Thompson & Preston, 2004), even when im- portant aspects of measurement have not been assessed (Blume, Galindo, &Walcott, 2007). The NAEP performance gap between White students and students of color has been greater for measurement than any other content domain (Lubienski, 2003). Though case studies have shown that deeper and more robust learning is possible with the right classroom ex- periences and teaching practices (Lehrer, Jaslow, & Curtis, 2003; Stephan, Bowers, Cobb, & Gravemeijer, 2003), we know little from empirical re- search about the factors that contribute to weak learning of spatial mea- surement in typical classrooms. This article explores the hypothesis that the nature of current elemen- tary curriculum materials, especially their procedural and conceptual con- tent and how they express that content to students, is one factor contrib- uting to students’ difficulties to learn length measurement. We will not claim a causal relationship between curricular content and students’ doc- umented learning challenges. Indeed, we devote substantial space to pre- senting a framework that identifies multiple factors that interact to cause the patterns of weak learning. Rather, our central claim is that a strong correlation exists between students’ challenges and the content of cur- rent U.S. elementary mathematics curricula, particularly with the docu- mented challenges that students face understanding length measurement. 1 In the United States, the first year of formal schooling is Kindergarten; in other countries, it is grade 1. Smith et al. in Cognition and Instruction 31 (2013) 3 To introduce and frame our curricular analysis, we first review the prob- lem of learning spatial measurement, then summarize what research has revealed (and not yet explained) about children’s understanding of length measurement specifically, and last describe a framework of factors that are jointly responsible for weak measurement learning. Measurement and Evidence of Weak Learning Our analysis focuses on length measurement, but the problem of learn- ing measurement extends beyond that specific quantity. That said, the measurement of space begins with length measurement, and more atten- tion is given to length measurement in the primary grades in the United States than any other quantity, as judged by state standards (Kasten & Newton, 2011). At its core, measurement is the assignment of a numerical value to a continuous quantity. Given a suitable unit, all similar contin- uous quantities (e.g., all lengths) are made discrete by segmenting them in unit parts. So all measures of continuous quantities have two compo- nents, the unit of measure and the number of those units that fill out or exhaust the particular quantity measured. In the United States, NAEP has consistently provided evidence of weak student learning of measurement. One indicator is performance on mea- surement items relative to other content domains. Although fourth graders have performed comparatively well on measurement, eighth graders’ mea- surement performance has remained low since 1990, along with geome- try and spatial sense (Thompson & Preston, 2004). Similarly, on the Third International Mathematics and Science Study (TIMSS), eighth grade U.S. students also scored significantly lower on measurement, both relative to other countries and to their own performance on other content domains (National Center of Educational Statistics, 1997). A second indicator has been performance on items requiring explanation or solution of nonroutine problems. Where U.S. fourth graders have been generally successful read- ing a ruler when one end of the object is aligned with the zero mark, they performed very poorly (20–25% correct over multiple assessments) when the object was aligned at a nonzero unit mark and the zero mark was not shown—frequently called the broken ruler task (Kloosterman, Rutledge, & Kenney, 2009). This result suggests that students do not understand the structure of rulers and may be simply reading off the ruler number at the end of the object whether it is appropriate or not. The performance gap be- tween White and minority students noted above was greatest for nonrou- tine items like the broken ruler task (Lubienski & Crockett, 2007). Smith et al. in Cognition and Instruction 31 (2013) 4 Smaller-scale studies targeting students’ reasoning have provided more insight into the nature of their struggles with measurement. Mul- tiple studies have shown that middle school students do not distinguish the perimeter (a length) from the area of simple geometric shapes (Chap- pell & Thompson, 1999; Woodward & Byrd, 1983). They take equal pe- rimeters as evidence of equal areas, apparently applying “same A, same B” reasoning (Stavy & Tirosh, 2000), and area responses have been at-
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