This open-ended investigation provides an opportunity for students to develop problem solving skills and explore patterns while applying number skills. Posed in the context of friends sending each other cards, it asks students to find how many cards are sent based on the number of friends, and to look for patterns that emerge in the results. The Teachers' Resources page offers rationale, suggestions for implementation, discussion questions, and ideas for extension and support. Be sure to check out the Solutions page to appreciate the potential range of student thinking.


  • Mathematics > General
  • Education > General

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Grade 3,oai:nsdl.org:2200/20140728160935950T,Make use of structure,NSDL,Grade 4,Grade 5,Addition,Strategies,Number concepts,Social Sciences,Arithmetic,Analyze and persevere,Concept formation,Process skills,Number and operations,Upper Elementary,Algebra,Word problems,Critical thinking,Subtraction,Multiplication,Patterns and sequences,Informal Education,Whole numbers,NSDL_SetSpec_ncs-NSDL-COLLECTION-000-003-112-027,Comparison of numbers,Reason abstractly,Practice Standards,Elementary School,Number patterns,Reason quantitatively,Algebraic thinking,Operations,Parity,Mental calculation,Communication,Mathematical language,Mathematics,Connections,Engineering,Problem solving,Education,Reasoning



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