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In this module students are introduced to place value using addition and subtraction up to the number 20. Students will extend work with addition and subtraction to the number 1-20, and learn some new strategies along the way. Students move from Level 1 strategy of counting all to the more efficient counting on. Now, they go beyond Level 2, counting on  to learn Level 3 decomposition and composition strategies, informally called make ten or take from ten.



Mathematical Practices

  1. Make sense of problems and persevere in solving them
  2. Reason abstractly and quantitatively.
  3. Construct viable arguments and critique the reasoning of others.
  4. Model with mathematics.
  5. Use appropriate tools strategically.
  6. Attend to precision
  7. Look for and make use of structure
  8. Look for and express regularity in repeated reasoning