This third Mystery Sums Sketchpad activity which opens on Geometer's Sketchpad, as well as on iOS with Sketchbook Explorer (cataloged separately) allows learners to use logic and early algebra reasoning skills to find the secret numerical value of ten letters, which are initially from 1-10, but this upper limit can be changed. Players encompass letters within a circle to reveal their sum. Students can play the game multiple times, with the computer generating new random values, or they can create challenges for each other to solve. A movie provides detailed instructions and downloadable PDF of teacher notes and student worksheets are also included.


  • Mathematics > General
  • Education > General

Education Levels:

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Grade 6,NSDL,Grade 5,Addition,Visual representation,Reason quantitatively,Mathematics,Arithmetic,Analyze and persevere,Process skills,Number and operations,Upper Elementary,Algebra,Express regularity,oai:nsdl.org:2200/20140728161114734T,Subtraction,Life Science,Composition and decomposition of numbers,Informal Education,Middle School,Vocational/Professional Development Education,NSDL_SetSpec_ncs-NSDL-COLLECTION-000-003-112-027,Practice Standards,Elementary School,Representation,Algebraic thinking,Chemistry,Operations,Deductive reasoning,Problem solving,Education,Reasoning



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