The Illinois Learning Standards (ILS) for math K-12 are designed to help students acquire a deep, conceptual understanding of core math content through focus, coherence, and rigor. Focus shifts teaching/learning from a mile long and an inch deep model to a deeper, richer understanding of fewer concepts. Coherence ensures math connections are made between grade levels and builds logical progression. Rigor promotes the equal balance of conceptual understanding, application, and procedural skill and fluency. Rigor: where challenge exceeds skill level.