This free math video is of my preschool aged daughter playing with Cuisenaire Rods in an unstructured way. She leads the way in how the play time goes. It is very important to let children have as much time as possible to play with the blocks in order to begin internalizing math concepts. She played with these for 6 months before I began to label them with number names.
Notice how my daughter is learning on her own that 10 tens is 100 and is learning the number bonds for 10 without realizing it.
No matter what age, when first learning about Cuisenaire Rods, people should be given plenty of time to use their imagination and just play. Make designs. Build buildings. Make dinosaurs. Anything you can think of!
As you can see, it is helpful to have a set of Base Ten Hundred Flats to go along with the Cuisenaire rods.