Comparing Structured and Unstructured Materials
There is a progression within fractions models from unstructured models (e.g. paper which needs active folding or cutting), to structured models (commercially produced pre-cut plastic pieces). This matches the progression with place value models for whole numbers; from unstructured models (e.g. pop-sticks which need active grouping with rubber bands) to structured models (e.g. MAB which has the base ten inherent in the pieces).
While structured materials are more convenient, students need to first experience unstructured materials and be actively involved in thinking and making decisions about their actions (grouping, folding, cutting, etc). Structured materials are certainly more convenient once this initial understanding is established and operations are being performed (e.g. adding whole numbers with MAB, or adding fractions with Fraction Strips).
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Unstructured materials |
Structured materials |
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Fraction materials |
Paper (circles, squares & strips) that needs to be partitioned (folded/ cut).
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Commercially produced sets of pieces (circles, squares & strips). |
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Strengths |
Good for introducing main ideas of partitioning as students are actively involved in thinking about and then creating parts. |
Useful for operations once partitioning ideas are firmly established. |
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Unstructured materials |
Structured materials |
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Whole Number materials |
Pop-sticks that need to be grouped and ungrouped with bands.
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MAB (Commercially produced plastic or wooden). |
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Strengths |
Good for introducing main ideas of place value as students are actively involved in thinking about and then creating groups. |
Useful for operations once grouping by ten ideas are firmly established. |