As they line up, they can do so by size. In art, children can arrange paint chips from light to dark. The attentive teacher can provide for and comment on these many daily experiences, bringing them naturally to the children's attention. Within the concepts of classification and seriation, children can develop skills related to patterning. Patterning skills begin by recognizing that there is a pattern.
Children soon are able to copy a pattern arranged by the teacher and verbalize the order.
They then may be able to continue the same pattern on their own. Creating an original pattern and even translating it into another form is a more sophisticated skill.