Given the growing numbers of Latino children entering the U.S. educational system, there is a need to understand the ways Latino parents support their children's early education. However, tools used to measure family engagement have been developed primarily with middle-income, English-speaking European American families in the United States. The present study builds upon prior empirical work with the Family Involvement Questionnaire-Early Childhood (FIQ-EC), a multidimensional scale developed for use with culturally diverse low-income families of young children. With a cross-site sample of 450 Latino parents of children in preschool through first grade, construct validity of the FIQ-EC was examined using Rasch methods and expert panel review. Results from Rasch analyses provided further support for the reliability of the factors comprising the FIQ-EC, as well as provided nuanced information regarding item and person functioning for this Latino sample. These results, in combination with expert panel reviews, suggested avenues for further item development when using this scale with low-income, Latino families. The current study has implications for validating measurement tools for use with diverse populations and also provides some clues about the role low-income, Latino families play in their children's schooling for consideration in future research.