Variability in children's early-learning home environments points to the need to better understand specific mechanisms of early mathematical development. We used a sample of 66 parent-preschool child dyads to describe parent-reported mathematical activities in the home and observed parent-child mathematical activities in a semi-structured play session. Data were examined to better understand the two methods of assessing the context of parent-child interactions related to mathematics. Parents reported engaging in a range of mathematical activities about 3-5 times per week, on average. Results from observed interactions indicated that parents engaged in math content/concept interactions in 32.5% of all observed intervals and children engaged in math content/concept interactions in 24.2% of all observed intervals. Although observed parent and child math content interactions were highly correlated, observed parent and child mathematical interactions were not correlated with parent-reported math activities.