This protocol guides the What Works Clearinghouse's (WWC) systematic reviews of evidence on interventions designed to improve the English language and literacy skills of students in kindergarten to grade 12. To conduct the systematic review, this protocol is used in conjunction with version 4.1 of the WWC Standards and Procedures Handbooks and the Study Review Protocol. This review focuses on educational interventions with a primary focus on improving English language and literacy skills--listening, speaking, reading, and writing--of students in kindergarten through 12th grade. These skills are critical to students' academic achievement and setting them on a path to successful high school graduation and readiness for college and careers.