Focus
Focus strongly where the Standards focus
The focus in the CCSSM is a response to the “milewide, inchdeep” nature of US math curriculum. The emphasis is on developing deep conceptual understanding, which lays the foundation for future learning The Standards call for a greater focus in mathematics. Rather than racing to cover topics in a milewide, inchdeep curriculum, the Standards require us to significantly narrow and deepen the way time and energy is spent in the math classroom. We focus deeply on the major work of each grade so that students can gain strong foundations: solid conceptual understanding, a high degree of procedural skill and fluency, and the ability to apply the math they know to solve problems inside and outside the math classroom.  from achievethecore.org 
The big shifts that the Common Core State Standards: Mathematics bring are increased focus, coherence, and rigor as the guiding principles for mathematics instruction and learning.
Focus in the SFUSD CurriculumSFUSD's Scope and Sequence is based on the Pearson Foundation System of Courses, which organizes the CCSSM into units of study that flow K–12. It reflects the coherence and focus of the CCSSM. The SFUSD Curriculum units are thematic and built around 4 rich math tasks.
