This study examined the developmental effects of early parental intrinsic and extrinsic motivational strategies on mathematics achievement scores obtained from White students compared to underrepresented minority students. A latent growth curve model was fit to data from the Longitudinal Study of American Youth (LSAY) with mathematics achievement assessed from 7th grade through 12th grade. Intrinsic parental motivational strategies were found to positively predict initial levels of mathematics achievement scores for White students but not underrepresented minority students. Extrinsic parental motivational strategies did not predict initial levels of mathematics achievement scores for either group of students. For White students, growth rate was found to be positively influenced by intrinsic and extrinsic parental motivational strategies. However, there is no evidence of this relationship for underrepresented minority students. This research contributes to an emerging literature relating developmental change processes to mathematics achievement. (Contains 5 tables, 3 figures and 2 notes.)