This interactive Java applet helps students understand place value and regrouping. Base 10 is the default, but users may choose to work in base 2 or 5. A user places (or removes) chips of three colors in three columns to represent numbers of up to three digits. When the number of chips in any column equals the base number, the user can exchange them for a chip in the next column. Similarly a chip of a higher value can be exchanged for the base number of chips of the lower value. The applet can be used to model addition and subtraction with regrouping.


  • Mathematics > General
  • Education > General

Education Levels:

  • Grade 1
  • Grade 2
  • Grade 3
  • Grade 4
  • Grade 5
  • Grade 6
  • Grade 7
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  • Grade 12


Grade 2,Grade 3,Grade 1,Make use of structure,NSDL,Grade 4,Grade 5,Addition,Early Elementary,Visual representation,Representation,Number concepts,Arithmetic,Concept formation,Process skills,Number and operations,Upper Elementary,Place value,Model with mathematics,Subtraction,Life Science,Composition and decomposition of numbers,Informal Education,Whole numbers,Middle School,NSDL_SetSpec_ncs-NSDL-COLLECTION-000-003-112-027,Comparison of numbers,Practice Standards,Elementary School,Reason quantitatively,Chemistry,Operations,Education,Number sense,Mathematics,Connections,Engineering,oai:nsdl.org:2200/20140728161052480T,Counting



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