The K–8 Publisher’s Criteria for the Common Core State Standards for Mathematics calls for at least 65% of time to be devoted to the major work of the grade with supporting work and additional work engaging students in the major work of the grade where appropriate. The designations for major, supporting, and additional work are by CCSSM clusters. For example, 3.OA.A Represent and solve problems involving multiplication and division, is the cluster covering standards 3.OA.A.1–3.OA.A.4. See http://achievethecore.org/shifts-mathematics for complete grade level focus breakdowns.
Math Trailblazers easily meets the focus on major work expectation. See the Focus on Major Work tables for each grade level for a closer look at where every cluster is explicitly addressed in 4th edition.