Surveys of 147 special education teachers and observations of 20 practicing teachers and 20 cooperating teachers were used to (1) determine which evaluation procedures are used most often by special education teachers in their evaluation of student progress, and (2) assess the adequacy of those procedures. Survey respondents indicated that they assess progress on individualized education program (IEP) objectives quarterly, that they rely on informal observation for assessing students' mastery of objectives, and that they are confident in their assessments of student performance. Observations of teachers during instruction corroborated these survey findings; teachers actually relied on and were confident in their informal observations of student performance on lesson objectives. Nevertheless, the observed teachers were highly inaccurate in their assessments of student mastery of lesson objectives and in their estimates of performance on lesson objectives. Implications for monitoring student progress are discussed. (Author/DB)