This article presents a pilot study of the 3M Preschool Routines Functioning Scale (3M) with Spanish children. Twenty teachers and 285 children, from 6 early childhood education centers in Valencia, Spain, participated. The teachers completed one 3M scale on each child in their classrooms. We studied the internal consistency of the scores of the scale items, the factor structure, and the sensitivity of the scale to identify differences on children's functioning level in relationship to their age. The 3M produced scores with strong internal consistency and an exploratory factor analysis resulted in 4 factors: Sophisticated Engagement, Personal–Social, Average Engagement, and Independence. The 3M total score had strong internal consistency, and the strong correlations among the factors and with the 3M total score suggested that the scale measured 1 dimension of child functioning, which we identified as participation.