"This site provides an extensive collection of free resources, math games, and hands-on math activities aligned with the Common Core State Standards for Mathematics. Our math printables are suitable for use in math centers, small group or whole class settings. Instructions for each activity are presented in large print on a task card in child-friendly language to enable students to work on tasks independently after a brief introduction to the task. All files are in PDF format and can be accessed using Adobe Reader.
Also available are Math Journal Tasks (K-5), Math Vocabulary Resources (Gds. 2-5) and Math Projects (Gds. 3-5) for teachers looking for ways to support students' math writing skills while developing key concepts and skills. See our E-Books page for more information on these resources."
"An app that allows me to view the CCSS quickly and on the fly. The app includes Math standards K-12 and LA standards K-12. The Math includes both traditional and integrated pathways."
Their site states: IXL's math skills are aligned to the 2010 Common Core State Standards, providing comprehensive coverage of math concepts and applications. With IXL's state standards alignments, you can easily find unlimited practice problems specifically tailored to each required standard.