This study looked at the effect of mother's educational level, child emotional difficulties, peer interactions, age, and gender on children's sophistication level of engagement. Eighty-six randomly selected children, aged between 36 and 72 months, and 20 teachers from 5 early childhood education centers in Valencia, Spain, participated in the study. Teachers reported on children's sophistication levels of engagement, interaction with peers, and emotional difficulties. Mothers reported on their highest educational level. The results indicated a direct effect of age, emotional difficulties, peer interactions, and mother's educational level on sophistication level of engagement. Emotional difficulties mediated the relation between mother's educational level and children's sophistication level of engagement, and peer interactions mediated the relation between sophistication level of engagement and age. Our results and those of other studies suggest promoting children's interactions with peers and emotionally secure environments as best practices for supporting children's higher sophistication levels of engagement in early childhood education routines.