Abstract Length Measurer

Organizes and synthesizes sets of objects based on perimeter or collections of complex bent paths based on overall length in two- or three-dimensional contexts to formulate and justify a valid argument. Can construct derived units with linear measures, such as miles per hour, and make appropriate unit conversions with derived measures. Computes perimeter or path length, including units and divisions of units including measures of non-integer values. Can explain that this subdivision process is potentially unlimited. Notices and is perturbed by geometric inconsistencies within polygons. Measures to the degree of precision allowed by a tool by estimating to a fraction of the smallest calibration mark provided on the instrument. 


You may see this:

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Other Examples:

  • When asked to check the validity of a hinged model for a triangle “case” with sides of 5, 7 and 12, the child can provide a rationale for excluding such cases by associating angle size and side length if the base is constant in length and the other sides must meet.
  • Child can use lower and upper bounds of linear estimates to order several curves by length.

Help your student become a(n) Abstract Length Measurer

Problems are presented that require all previous concepts and skills, now also including fractions of units, precisions of measurements, translations between units, and derived units (e.g., kilometers per hour).

Special Thanks To

Institute of Education Sciences
The research reported here was supported by the Institute of Education Sciences, U.S. Department of Education, through grant numbers R305K050157, R305A120813, R305A110188, and R305A150243. to the University of Denver. The opinions expressed are those of the authors and do not represent views of the Institute or the U.S. Department of Education.