This document discusses using Cuisenaire rods to develop conceptual understanding of mathematical concepts. It provides examples of spatial puzzles and activities with the rods to help children decompose and recompose shapes. These activities build the foundation for understanding geometry. Examples also show using the rods to represent numbers in different ways, compare quantities, explore properties like commutative and distributive, build patterns, use measurement conversion and develop fraction concepts. The document emphasizes that experiences with the manipulatives are important for building number sense and geometry understanding in children.