A study investigated alternative methods of assessing student language skills in Arlington County (Virginia) public schools' Spanish/English two-way bilingual partial immersion program, with the objective of improving information for developing more effective teaching. A team of teachers from each participating school worked with researchers to develop, pilot, field-test, and evaluate alternative assessment methods, including oral and written language rubrics in both Spanish and English. In addition, the research team, which included elementary and middle school teachers, a special education teacher, district administrators, and researchers, explored ways in which using alternative assessment methods might inform or otherwise influence instructional practices. The report describes the context of the school system and bilingual education program, chronicles the project, and summarizes results as they relate to specified project goals. Early termination of the project limited assessment of the rubrics' validity. Unanticipated results and their implications for classroom instruction are also noted. Appendices comprising approximately 75% of the report include English and Spanish versions of the rubrics (grades 1-5) and supporting classroom materials and forms. Contains 11 references. (MSE)