A comparison of achievement and personal adjustment of Spanish-speaking students in an experimental bilingual school environment at the first grade level was the purpose of the Harlandale instructional project. This evaluation report presents comparative data from the testing program used to establish the effectiveness of bilingual education when compared to traditional English-only instruction. The comparative data also includes behavioral observations by the teacher, attendance and promotion data, and pupil history. Statistical comparisons are made on all test results of the pre- and post-testing periods. The results of the project tend to reflect favorably on bilingual instruction, and recommendations were made to expand and continue research in the program. (DK)