This study estimated male-female and Black-White achievement gaps without accounting for low test motivation, then compared those estimates to ones that used several approaches to addressing rapid guessing. Researchers investigated two issues: (1) The differences in rates of rapid guessing across subgroups and (2) How much achievement gap estimates change when rapid guessing is addressed. The study used reading and mathematics scores from the Measures of Academic Progress (MAP), a test administered in nearly all U.S. states. Results suggest that rapid guessing occurs at very different rates across subgroups. However, rapid guessing generally has a mild effect on gaps estimates, although there are cases where failing to account for low test motivation may be impacting fundamental inferences made based on gaps. As part of the second question, differences across approaches to accounting for rapid guessing were examined. Results suggest that rapid guessing occurs at very different rates across subgroups. However, rapid guessing generally has a mild effect on gaps estimates, although there are cases where failing to account for low test motivation may be impacting fundamental inferences made based on gaps.