The paper examines interpretive aspects of English non-uniformity among fifth and sixth grade Native Americans at Laguna Elementary School, Laguna, New Mexico. Speaker assessments of instances of uninflected "be" are ordered to form an implicational scale. The variability in the students' assessment pattern is compared to previous inter-ethnic testing and scaling. Considerable lack of mid-range progressions is documented in the response population. Two polar groups of students are identified by the patterning of their assessments. Although social variables are reported not to condition this non-uniformity, the addition of assessments from adult community members fills in mid-range progressions. This suggests either that non-adults can start at two ends of the constructed English continuum and still converge in a common lectal area as adults, or that rapid linguistic change has caused non-adults to diverge from adult patterns or standards. Practical aspects of non-uniformity and developmental or change stages thereof are potentially far-reaching for curriculum planning, development of instructional strategies and techniques of measurement and evaluation. Additional kinds of questions are raised, and data sources necessary for further interpretive exploration are identified. (Author/AM)