On Core Mathematics develops students' understanding of the Common Core State Standards for Mathematics in an interactive format. Each grade-level bundle includes a Student Worktext and Teacher Edition. In Grades K–5, students actively participate in lessons that use manipulatives and step-by-step models to develop an in-depth understanding of the Common Core State Standards for Mathematics. In Grades 6–Algebra 2, students gain a deeper understanding of the Common Core State Standards for Mathematics by exploring, interacting, and reflecting on the skills and concepts presented.