This study was inspired by the final regulations for the No Child Left Behind Act (NCLB) indicating that each state has the option to develop a new assessment for students whose disabilities have kept them from obtaining proficiency. Sets of high school science achievement items were enhanced for the new test. A 3-by-2, within subjects, experimental design was used with 400 participants from 3 states. Although items remained connected to grade-level content standards, in the enhanced condition they were easier for all groups. Changes in measurement precision were mixed for students in the group eligible for the new examination. Participants tended to report that individual enhancements made items easier, but that packages of enhancements did not affect the difficulty of items. (Contains 8 tables.)