Math
First Grade
Unit 1
How can I break apart a quantity and see the parts of the whole?
Students understand that quantities can be broken apart to show a part-whole relationship and that this relationship can be represented by addition.
In this unit, students focus on breaking apart quantities to recognize the relationship between parts and wholes. They look for relationships between the partitions of a quantity (such as commutativity and partitions that are one more and one less) and use patterns to prove that they’ve found all the partitions. As students work with parts and wholes, they model the relationships with concrete materials, part whole models, drawings, and equations. They invent real-world situations in which part whole relationships arise, and they connect the idea of parts and wholes to addition. This builds the foundation for learning number combinations (addition and subtraction facts).
Why is it important to develop flexibility with addition and subtraction strategies?
Through the understanding of relationships between knowns and unknowns within an addition or subtraction problem, students are able to flexibly apply a variety of strategies to solve problems with increasing accuracy and efficiency.
In this unit, students analyze a variety of reasoning strategies (including doubles, near doubles, and anchoring to five and ten), along with an understanding of even and odd, to build fluency for addition and subtraction within 20. They will use models (unifix cubes, drawings, number lines, bar models, part-part-whole models, and equations) to make sense of a variety of one and two-step addition and subtraction word problems structures (Add To/Take From, Put Together/Take Apart, and Additive Comparison) and use their reasoning strategies when solving for the unknown.