In this article, we describe results of a reanalysis of two randomized studies that tested the effects of enhanced anchored instruction (EAI) on the fractions computation performance of students in special education resource rooms and inclusive mathematics classrooms. Latent class analysis and latent transition analysis classified students according to error subtypes and tracked their performance patterns. Results indicated that EAI was more effective than business as usual in reducing combining errors (e.g., adding denominators) and denominator errors (e.g., not finding common denominator) of students with disabilities (SWD) and students without disabilities in both settings. SWD in inclusive classrooms scored higher on the pretest than SWD in resource rooms, but EAI reduced the disparity on the posttest. An important additional finding revealed that the SWD who received more support from special education teachers in inclusive classrooms scored higher and made fewer errors than the SWD who were provided only limited support. [For the full text grantee submission, see ED578254.]