In the United States, students who are deaf or hard of hearing (SDHH) are required to participate in high-stakes standardized assessments under No Child Left Behind reforms. In 2006-2007, states added science to reading and mathematics as a tested content area. Many SDHH participate in these assessments using testing accommodations, but teachers have few evidence-based resources to draw upon when making accommodations decisions. Two research questions guided this study: (a) What were patterns of SDHH 2006-2007 test accommodations use in state standardized assessments in mathematics, reading, and science? (b) What evidence did teachers use to determine the effectiveness of accommodations for SDHH? A total of 290 participants described their assessment practices with SDHH via an online and paper-and-pencil survey. Extended time, small group, and test directions interpreted were the most frequently used accommodations by SDHH, but there were some different patterns in science for accommodations that included changes to the test items. Teachers reported both student satisfaction and test score validity epistemologies of accommodations' effectiveness.