RIGOR was developed by Margarita Calderón, Ph.D., Professor Emerita at Johns Hopkins University School of Education. The RIGOR intervention resources are based on Dr. Calderón’s studies of English-language acquisition and her ongoing work with middle and high school teachers of English learners in New York City. The author of more than 100 articles, chapter books, and teacher training manuals, Dr. Calderón also wrote the well-known professional book Teaching Reading to English Language Learners, Grades 6–12. She has been a member of the National Literacy Panel on Language-Minority Children and Youth, and she frequently presents at conferences of the International Reading Association and Teachers of English as a Second Language

Grades 2-4