Grade 2: Carol’s Numbers


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Content Standards

2.NBT.1, 2.NBT.3, 2.NBT.4


Standards for Mathematical Practice

MP.1   Make sense of problems and persevere in solving them.

MP.3   Construct viable arguments and critique the reasoning of others.

MP.6   Attend to precision.


This 4-5 week unit “Carol’s Numbers” from the NYC Dept. of Education involves understanding the meaning of base ten and using that understanding to solve number and real life problems. The number line is used as a tool to help articulate understanding of base ten and to solve problems using addition and subtraction of numbers less than one hundred. The focus is on the big idea around groups of ten. Strategies will involve applying number properties including distributive, associative, and commutative.


Connecticut teachers should be aware that the unit is considered a high quality resource if used with the following suggestions:

  • Teachers may use this unit outline as presented or integrate parts of this unit into a related pre-existing curriculum unit.
  •  Guidance for differentiation and extensions are included (particularly, accommodations for assessment) however teachers will have to develop differentiated instruction at the lesson level.


Focus: The unit centers on the major work/concepts of the grade.

Alignment: Content and Practice Standards are instructed and assessed. Rubrics with student work, descriptions and instructional implications are included. Pre-Assessment, Formative, and End of Unit Performance assessments are included. General strategies for instruction of English Language Learners and Students with Disabilities are included.