The Illinois State Board of Education (ISBE) is committed to the cognitive, linguistic, and socio-emotional development of all children in Illinois. ISBE's Multilingual Department is focused on ensuring that students with diverse linguistic repertoires and those who may benefit from additional support have equitable access to academic instruction…

Number relationships, which go far beyond counting skills, refer to the ability to represent a quantity in multiple, flexible ways. It is arguably among the most important mathematics concepts in number and quantity. The current study examined the effectiveness of number relationships instruction in preschool classrooms. Participants included 73…

This article provides practical guidance for researchers who are designing studies that randomize groups to measure the impacts of educational interventions. The article (a) provides new empirical information about the values of parameters that influence the precision of impact estimates (intraclass correlations and R[superscript 2] values) and…