Arco Iris follows the Common Core State Standards. You can find more information on the standards on the ODE website.
"What do parents need to know about the Common Core State Standards? How will they affect teaching and assessing mathematics and English language arts? What are the benefits and what can parents do to prepare for the CCSS? These and other questions are answered in the March 2011 Spotlight on the Common Core State Standards—a series published by Education Northwest to keep regional stakeholders informed about this important initiative."