-Makes mathematics education research on fraction concepts accessible and understandable to pre-service and in-service teachers of grades K-8, allowing teachers to understand evidence in student work and make better instructional decisions. -Uses extensive annotated samples of student work, helping teachers improve their ability to recognize and assess student errors and misconceptions, as well as their understanding, learning, and fluency of fraction concepts. -Built off the wide-scale research gathered in the Ongoing Assessment Project (OGAP), drawn from hundreds of teachers and thousands of examples of student work. -Each chapter includes student work samples and vignettes to illuminate the research, guidance on CCSSM standards, end of chapter questions, professional development activities, and instructional links that help teachers relate concepts back to their own instructional materials and programs. -This edition has been updated throughout with the latest research, CCSSM standards, additional examples and vignettes, and more.

-Makes mathematics education research on fraction concepts accessible and understandable to pre-service and in-service teachers of grades K-8, allowing teachers to understand evidence in student work and make better instructional decisions. -Uses extensive annotated samples of student work, helping teachers improve their ability to recognize and assess student errors and misconceptions, as well as their understanding, learning, and fluency of fraction concepts. -Built off the wide-scale research gathered in the Ongoing Assessment Project (OGAP), drawn from hundreds of teachers and thousands of examples of student work. -Each chapter includes student work samples and vignettes to illuminate the research, guidance on CCSSM standards, end of chapter questions, professional development activities, and instructional links that help teachers relate concepts back to their own instructional materials and programs. -This edition has been updated throughout with the latest research, CCSSM standards, additional examples and vignettes, and more.