The effect of testing accommodations, such as extra time, oral reading of the assessment, or small group testing, on the participation and performance levels of limited-English-proficient students (LEP) on the Rhode Island Grade 4 Mathematics Performance Assessment was studied. A pilot study was conducted with 22 classes of students to provide preliminary evidence of the relative validity of both the performance assessment and the traditionally used Metropolitan Achievement Test (MAT) for language-minority students in comparison with general education students. The statewide data show a clear increase in the number of LED and special education students participating in the performance assessment compared to those who took the MAT. This was probably a result of the availability of accommodations or the test instructions, which stressed full inclusion. Accommodations consistently raised the relative position of LEP and special education students compared to their position on the MAT in the past. In the operational statewide assessment there was no way to evaluate the validity of the achievement gains associated with the use of accommodations, but for the most part the level of gain appeared reasonable. In the pilot sample, teachers' mathematics grades and teachers' standards-based ratings in mathematics could be used as validity criteria to evaluate the performance assessment and the MAT. Evidence supports the validity of the tests for general education students and for language-minority students, but is not as strong for the validity for LEP students. For a first effort, the inclusion of LEP students in the Rhode Island fourth-grade assessment appears to have been reasonably successful. An appendix discusses method to evaluate differential item functioning. (Contains 13 tables, 17 figures, and 19 references.) (SLD)