A fundamental claim for Common Core State Standards (CCSS)-aligned assessments is that they will lead to better teaching practices. The purpose of this study is to seek evidence in support of this claim by surveying teachers about their instructional practices, test preparation strategies, and test score use both before and after the introduction of CCSS-aligned assessments. Baseline and trend data were collected via five Web-based surveys, administered over 2 years to elementary and middle school English language arts and mathematics teachers in one state, New Jersey. Responses to the first three surveys (n[subscript 1] = 402 teachers, n[subscript 2] = 469 teachers, and n[subscript 3] = 175 teachers from 4% to 6% of New Jersey schools) are summarized and described; results from the remaining surveys are omitted due to low response. Challenges to collecting empirical evidence in support of the validity argument and theory of action for a new assessment are discussed.