A study reports on the first 3 years of a 5-year study focusing on characteristics of educational practice that accompany student achievement in English language arts in middle and high schools. The study attempts to specify features of instruction that make a difference in student learning by comparing high-achieving and under-achieving schools which are otherwise similar. It involved 19 middle and high school English programs in Florida, New York, and California schools exhibiting diversity in population, educational problems, and approaches to improvement, and it was organized as a nested case design with the program as a case and the class including teachers and students, as cases within. Findings suggest higher achieving schools are characterized by instructional programs in which: (1) skills and knowledge are taught in multiple types of lessons; (2) tests are deconstructed to inform curriculum and instruction; (3) within curriculum and instruction, connections are made across content and structure to ensure coherence; (4) strategies for thinking and doing are emphasized; (5) generative learning is encouraged; and (6) classrooms are organized to foster collaboration and cogitation. Contains 9 tables and 36 references. Appendixes describe schools involved in the study and list related reports. (EF)