Resources and Tools for Elementary Math Specialists and Teachers
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Find the Secret Number-Developing a Search Strategy

This webpage contains a link to a downloadable Geometer's Sketchpad activity that familiarizes students with inequality signs (> and <) and introduces the use of the variable x to represent an unknown value. Students are challenged to deduce a number by collecting and analyzing clues that narrow its range of possible values in the fewest guesses. The page also includes a three-minute instructional video and downloadable PDFs of teacher notes and student worksheets. This activity opens on Geometer's Sketchpad as well as on iOS with Sketchbook Explorer (cataloged separately).
Contributed by: Daniel Scher - Author, KCP Technologies, Inc, a McGraw-Hill Co. - Publisher
Math TopicAlgebraic Thinking, Number Sense, Number Concepts, Mathematical Practices, Mathematical Processes
Grade Level1, 2, 3, 4, 5, 6+
Resource TypeActivity, Instructional Strategy, Lesson Plans, Video

  • Additional Information
    • AudienceEducator, Learner
    • LanguageEnglish (USA)
    • Education TopicTeaching strategies
    • Interdisciplinary Connection
    • Professional DevelopmentNo
    • ContributorDaniel Scher - Author, KCP Technologies, Inc, a McGraw-Hill Co. - Publisher
    • Publication Date2013
    • RightsCopyright (c) 2013 KCP Technologies Inc., a McGraw-Hill Education Company
    • AccessFree access
  • Standards
    • Common Core State Standards for Mathematics

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