Young children instinctually notice attributes: shape, size, color, length, type, and other characteristics of objects. They also notice that items can have attributes in common (these are all red) and not in common (these are all red but those are all blue). With practice, children are able to sort collections of objects by one attribute, like color, and then by two or more attributes. For example, they can sort the items that are large, red squares from the items that are large, red triangles. Help children think flexibly about their sorting! After they sort according to an attribute, or sorting rule, ask, "Can you think of another way that we could sort these items? If we sorted these items in a different way, would we get the same results?"