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In this online activity, learners will explore size estimation in one, two and three dimensions. Multiple levels of difficulty allow for progressive skill improvement. This activity includes an online simulation, sample learning goals, and translations in over 20 languages.

Quick Guide

Preparation Time:
Under 5 minutes

Learning Time:
10 to 30 minutes

Estimated Materials Cost:

Age Range:
Ages 6 - adult

Resource Types:
Activity, Game, Simulation

Arabic, Basque, Chinese, Croatian, Danish, Dutch, English, Estonian, French, Greek, Hebrew, Hungarian, Italian, Korean, Persian, Polish, Portuguese, Serbian, Slovak, Spanish, Turkish, Vietnamese

Materials List (per student)

  • Computer with online access, current Macromedia Flash software, and mouse


  • Mathematics
    • Geometry
      • Plane Geometry
      • Solid Geometry
    • Measurement
      • Units of Measurement
      • Size and Scale
      • Circles
      • Polygons
    • Number and Operations
      • Multiples and Factors
    • Representation

Informal Categories

  • Games


To use this activity, learners need to:

  • see
  • read
  • use keyboard
  • use mouse

Learning styles supported:

  • Involves hands-on or lab activities


Foreign language versions of this resource:

Access Rights:

  • Free access


  • Dubson, Michael; Gratny, Mindy


  • All Rights Reserved, University of Colorado, ©2011

Funding Sources:

  • The William and Flora Hewlett Foundation
  • National Science Foundation
  • Excellence Center of Science and Mathematics Education at King Saud University
  • O'Donnell Foundation
  • Wireless Generation


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