1 mapping children’s understanding of mathematical equivalence roger s. taylor, bethany...
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Mapping children’s Mapping children’s understanding of understanding of
mathematical equivalencemathematical equivalence
Roger S. Taylor, Bethany Rittle-Johnson, Roger S. Taylor, Bethany Rittle-Johnson, Percival G. Matthews, Katherine L. Percival G. Matthews, Katherine L.
McEldoonMcEldoon
• Goal of “Algebra for All” motivated National Mathematics Panel (2008) report on how to improve students’ readiness for algebra
• To meet this goal, must re-conceptualize algebra as a continuous strand from elementary through high school (NCTM, 2000)
Algebraic ReasoningAlgebraic Reasoning
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• Previous research has shown that knowledge of the equal sign and equivalence (or equality) is critical for learning algebra (Carpenter, et al., 2003; Knuth, Stephens, McNeil, & Alibali, 2006)
• Equivalence is the principle that two sides of an equation represent the same value
• Provides the foundation for two key algebra proficiencies (Kieran, 1992):
• Understanding the equivalence of expressions
• Competence at performing the same operation on both sides of an equation
• Is accessible to elementary school children (Baroody & Ginsburg, 1983; Jacobs et al., 2007)
Algebra & EquivalenceAlgebra & Equivalence
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• Many children view the equal sign operationally, as a command to carry out arithmetic operations (Baroody & Ginsburg, 1983; Carpenter, et al., 2003; McNeil & Alibali, 2005)
• Define “=“ as meaning “add up the numbers”
• Solve equations incorrectly when operations on the right side of the equal sign, such as: 3 + 5 = __ + 6
• Reject number sentences such as 3 + 5 = 5 + 3
• Children need to develop a relational view of the equal sign
Two views of EquivalenceTwo views of Equivalence
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• Knowledge of equivalence assessed through 3 main components (e.g. Alibali, 1999; Falkner, Levi, & Carpenter, 1999; Li, Ding, Capraro, & Capraro, 2008; McNeil, 2007; Rittle-Johnson & Alibali, 1999; Weaver, 1973)
1. Meaning of the Equal Sign
• Knowledge of equivalence and the equal sign
2. Recognizing Valid Equations
• Knowledge of allowable equation formats
3. Solving Equations
• Problem solving ability with different equation formats
Three Components of Three Components of EquivalenceEquivalence
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• Develop framework for assessing & interpreting students’ level of understanding of mathematical equivalence
• Validate assessment
• Initial phase of research project: Creation & validation of Construct Map (Wilson, 2005)
Focus of StudyFocus of Study
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Overview of the Overview of the ConstructConstruct
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Setting & Data CollectionSetting & Data Collection
• School: Urban, parochial, serving working-to middle-class, predominantly Caucasian students
• Written assessment (single period)
• Administered to 181 students in 10 2nd-6th grade classrooms (2 per grade)
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Construct Component: Construct Component: Equal Sign Equal Sign
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Equal Sign Wright MapEqual Sign Wright Map
Respondents | Items
HigherAbility
HigherDifficulty
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Equal Sign Wright MapEqual Sign Wright Map
Respondents | Items
ES4: (L2) Which answer choice below would you Put in the empty box to show that two nickels are the same amount of money as one dime? Circle your answer.
a)+b)=c)5¢
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Equal Sign Wright MapEqual Sign Wright Map
Respondents | Items
ES1: (L3) What does the equal sign (=) mean?
ES5: (L3) Is this a good definition of the equal sign? Circle good or not good.• The equal sign means the same as.
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Equal Sign LevelsEqual Sign Levels
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Construct Component: Construct Component: Recognizing Valid EquationsRecognizing Valid Equations
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Recognizing Equations Recognizing Equations Wright MapWright Map
Respondents | Items
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Recognizing Equations Recognizing Equations Wright MapWright Map
Respondents | Items
RE2b: (L2) For each example, decide if the number sentence is true. In other words, does it make sense?• 8 = 8
RE2h: (L3) For each example, decide if the number sentence is true. In other words, does it make sense?• 6 + 4 = 5 + 5
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Recognizing Equations Recognizing Equations LevelsLevels
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Construct Component: Construct Component: Solving EquationsSolving Equations
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Solving Equations Wright Solving Equations Wright MapMap
Respondents | Items
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Solving Equations Wright Solving Equations Wright MapMap
Respondents | Items
SE5: (L2) 8 = 6 + __
SE10: (L3) 3 + 6 = 8 + __
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Solving Equations LevelsSolving Equations Levels
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Three Construct Three Construct ComponentsComponents
Solving EquationsRecognizing Valid EquationsMeaning of the Equal Sign
• Developed mathematical equivalence construct that consists of three components that seem to develop at different rates
• Created Construct Map
• Provides framework for assessing & interpreting students’ knowledge of mathematical equivalence
• Helped refine our thinking of what makes items hard
• Provides educational researchers and practitioners with a criterion-referenced interpretation of instructional assessments and student performance
SummarySummary
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• Test-retest reliability
• Convergent and divergent validity
• Design of instructional interventions
• Utilization of assessment in other research projects
Future ResearchFuture Research
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