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Phase 7: Mastery

Lessons 126-150 · Phase 7 covers two-digit addition and subtraction (with and without regrouping), word problems, and mixed practice for complete mastery.

Concepts Introduced

SymbolLessonTypeExample
two-digit + two-digit126operation34 + 25 = 59
regrouping (carrying)130concept28 + 15 = 43
two-digit − two-digit135operation56 − 23 = 33
regrouping (borrowing)140concept42 − 17 = 25
word problems145applicationSam has 12 apples. He gives away 5. How many are left?

Skills

  • Two-digit addition without regrouping
  • Two-digit addition with regrouping (carrying)
  • Two-digit subtraction without regrouping
  • Two-digit subtraction with regrouping (borrowing)
  • Solving addition and subtraction word problems
  • Mixed practice with all four types

Tips for Teachers

The child is now doing real arithmetic. Regrouping (carrying and borrowing) is the hardest concept in this entire program. Use place value charts and base-ten block drawings. Do not rush.

What to Expect

By the end of Phase 7, the learner has completed the full K–4 math foundations curriculum. They can add and subtract two-digit numbers, solve word problems, and have automatic recall of basic facts.

Lessons in This Phase

126 2-digit + 2-digit 127 2-digit + 2-digit 128 2-digit + 2-digit 129 2-digit + 2-digit 130 carrying 131 carrying 132 carrying 133 carrying 134 carrying 135 2-digit − 2-digit 136 2-digit − 2-digit 137 2-digit − 2-digit 138 2-digit − 2-digit 139 2-digit − 2-digit 140 borrowing 141 borrowing 142 borrowing 143 borrowing 144 borrowing 145 word problems 146 word problems 147 word problems 148 word problems 149 mastery review 150 mastery review