This paper focuses on selected findings from a study that explored the use of multiplication and division with 34 five- and six-year-old children from diverse cultural and linguistic backgrounds. The focus of instructional tasks was on working with groups of ten to support the understanding of place value. Findings from relevant assessment tasks and children's work highlighted the importance of encouraging young children to move from unitary (counting by ones) to tens-structured thinking. [For the complete proceedings, see ED597799.]