In this two player online game, students combine math skills and strategy to practice estimating answers to calculation problems. For each correct answer, the player places a colored ball on a 10-by-10 grid. The first person to place four balls of his or her color together in a row or diagonally wins. Students choose how close the estimate must be, response time limit, and whether addition, multiplication, and/or percentage are involved. Problems range from addition with two and three digit numbers to percentages. From the game page, What, How, and Why buttons open sections that explain the activity's purpose, function, and where the mathematics fits into the curriculum, including information about the NCTM grades 6-8 standard for number and operation. Also included are links to related lessons and discussion questions about making good estimates and how estimation is used in real life. Copyright 2005 Eisenhower National Clearinghouse


  • Mathematics > General
  • Education > General

Education Levels:

  • Grade 1
  • Grade 2
  • Grade 3
  • Grade 4
  • Grade 5
  • Grade 6
  • Grade 7
  • Grade 8
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Grade 3,Grade 6,NSDL,Grade 4,Grade 5,Addition,Grade 8,Percent,oai:nsdl.org:2200/20120114184336354T,Number concepts,Mathematics,Arithmetic,Grade 7,Number and operations,Upper Elementary,NSDL_SetSpec_1007936,Multiplication,Informal Education,Whole numbers,Middle School,Elementary School,Operations,Education



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