In an article in the most recent Reading Research Quarterly, Pearson, Hiebert, and Kamil describe difficulties with current vocabulary assessments. They argue that words on vocabulary assessments are typically chosen to discriminate across students, not to establish whether students have knowledge about particular domains of vocabulary. If educators are to make a dent in the vocabulary gap that currently exists between low- and high-achieving students, disciplined ways of selecting words for instruction—and assessments—are needed. Among the guidelines that Pearson et al. propose for assessing (and instructing) vocabulary in a strategic manner are a focus on: (a) words that are, indeed, unknown, to students; (b) thematic clustering of vocabulary; (c) morphological families; and (d) providing vocabulary in a variety of different and rich textual contexts.
Pearson, P.D., Hiebert, E.H., & Kamil, M.L. (2007). Vocabulary assessment: What we know and what we need to know. Reading Research Quarterly, 42 (2), 282-296. [A copy of this article for individual use is available in the TextProject Library at http://www.textproject.org/library/articles/vocabulary-assessment/]