Our work with education leaders emphasizes the development of design experiments, the careful review of evidence, and the articulation of lessons learned. Our work with classroom teachers emphasizes the creation of school-based and district-wide structures that support professional learning and improved practice. All CLLC work is grounded in the following principles:

• Educators' active engagement in learning is essential to institutional improvement and professional growth;
• Educators' knowledge about instruction and student understanding is broadly distributed within and across schools;
• Educators learn best when what they learn is closely connected to practice;
• Educators' learning is enhanced by working with knowledgeable peers who question, challenge, and support one another.