This final report on the Preliminary Evaluation of Planned Variation in Head Start According to Follow Through Approaches is a detailed account of the field testing and implementation activities performed during the 1969-1972 period, with emphasis on the second and third years. The sections of the report are as follows: I. Introduction; II. Background and Overview; III. Fall 1969 Testing Activities; IV. Spring 1970 Testing Activities; V. Fall 1970 Testing Activities; VI. Spring 1971 Testing Activities; VII. Fall 1971 Testing Activities; and VIII. Spring 1972 Testing Activities. Ten appendixes provide: A. through F., Fall and Spring Communications 1969-1972; G. Supplemental Instructions for Field Staff, Spring 1971; H. Record of Test Data and Information Forms Transmitted to Huron Institute; I. Quizzes and Answer Sheets for Spring 1972; and J. SRI Field Supervisor Site Report Forms. Data are presented in 18 tables. (DB)