We present the PERCEPT-R corpus, a labeled corpus of child speakers of American English with typical speech and residual speech sound disorders affecting rhotics. We demonstrate the utility of age-and-gender normalized formants extracted from PERCEPT-R in training support vector classifiers to predict ground-truth perceptual judgments of "rhotic” (i.e., dialect-typical) and "derhotic” phones for novel speakers (mean of participant-specific f-metrics = .83; SD = .18, N = 281).