This document provides the technical appendix that accompanies the study, "Student Experiences in English Corequisite Remediation versus a Standalone Developmental Education Course: Findings from an Experimental Study in Texas Community Colleges. Research Report. RR-A810-1" (ED612531). Between fall 2016 and fall 2018, the authors conducted an evaluation of English corequisite models in five Texas community colleges. Students were randomly assigned to corequisite remediation (a college-level English composition course paired with one to three hours of weekly academic support) or to a standalone developmental education course (an integrated reading and writing course that did not offer students transferrable credit). The authors collected student-level administrative and survey data to examine contrasts in experiences quantitatively, and we also gathered qualitative data to shed light on these experiences. In this technical appendix, the authors provide a description of the randomized control trial and the data sources that were used for the report to examine student experiences. They also provide more-detailed findings on the key measures from the student-level administrative and survey data and some of the results from the faculty survey to supplement the findings present in the report.