This study determined the pupils' proficiency and Language Assessment performance in using Iloko in Ambaguio District, Division of Nueva Vizcaya.

Descriptive - correlation design was used in the study. Ten public elementary schools, 153 pupils and 30 Grades 1, 2 and 3 teachers were the sources of data and respondents of the study. Data were gathered using questionnaires, interview guide and survey guide, and data were also taken from CB-PAST ratings forms, Form 137 and the pupils' language assessment performance report. Descriptive statistics such as frequency, percentage, and mean were used to describe the profile and to determine the proficiency level of the subjects of the study in their Mother Tongue subject and the language assessment performance in using lloko. Ranks were used to determine the problems, solutions and teachers' suggestions in using Iloko as medium of instruction. Pearson Product Moment Correlation Coefficient was used to determine the relationship between pupils' profile, teachers' profile and schools' profile variables and the pupils' language assessment performance. Multivariate Linear Regression using Stepwise procedure was used to determine the predictors of pupils' language assessment performance.

The specific component of pupils' language assessment was found significantly related to pupils' sex, pupils' proficiency level in mother tongue subject, teachers' years of service and teachers' performance. The number of academic classrooms, teaching position of Grades 1, 2 and 3 teachers, years of service of the teachers and the performance of the teachers were the predictors of pupils' language assessment performance.

Thesis (Master of Education - Educational Administration)

Includes appendices and bibliographical references