In second grade, students continue to build a mathematical foundation that is critical to learning higher mathematics.
4 Critical Areas of Instruction
In second grade, instructional time focuses on four critical areas: (1) extending understanding of place value to the hundreds place; (2) building fluency with addition and subtraction; (3) using standard units of measure; and (4) describing and analyzing shapes (National Governors Association Center for Best Practices, Council of Chief State School Officers [NGA/CCSSO] 2010).
Students also work toward fluency with addition and subtraction within 20 using mental strategies and within 100 using strategies based on place value, properties of operations, and the relationship between addition and subtraction. They know from memory all sums of two one-digit numbers.
When educators talk about performing an operation “within” a number, for example “within 20”, they mean the answers are no larger than 20. Being fluent with something in math means students can perform the operation reasonably fast and accurately.