SIM tools, when used in combination with additional interventions to affect school-wide change, may be implemented through tiered systems of support. One systematic approach, developed at the CRL, is called the Content Literacy Continuum™ (CLC). CLC is a coordinated, school-wide approach to improving literacy for all students in secondary schools, enabling them to meet higher standards. Based on five levels and focused on helping schools use their data to develop and sustain a comprehensive and integrated approach to literacy, CLC's goal is to ensure that schools are empowered to develop the infrastructure necessary to identify, develop, and offer the multi-tiered resources, services, and supports essential to a literate, successful school community.