This is the appendix for the report, "The Impact of Word Knowledge Instruction on Literacy Outcomes in Grade 5." District leaders in a large urban school district in central Florida wanted to examine the efficacy of a new curriculum designed to enhance the word knowledge of grade 5 students so as to improve reading achievement. The new curriculum, called Word Knowledge Instruction (WKI), consists of 15-minute lessons 4 days a week for 20 weeks. The lessons address state standards and cover 20 prefixes and suffixes. Thirty-nine schools participated in the study, with 92 English language arts (ELA) teachers in high-poverty schools randomly assigned within schools either to use WKI or to continue to use their standard ELA curriculum. This appendix describes the study data, intervention, analytic sample, and analyses used to assess the impact of Word Knowledge Instruction (WKI) on student literacy outcomes in grade 5. One appendix is included in this document: Data, intervention, sample, and methodology. [For the full report, see ED611683. For the study snapshot, see ED611684.]