Sorting and classifying activities may seem like child's play, but these early developmental activities help to form basic skills on which many future math concepts build. These kindergarten activities help a child to form number sense, the innate ability to understand numerical connections and relationships. Without this basic number sense, students struggle in future mathematical learning. By providing a variety of ongoing sorting and classifying activities, kindergarten students enthusiastically engage in learning on which future math skills build.

## Common Categories and Attributes

Typically, children start out sorting and classifying objects into simple categories such as shape, color and size. These basic categories are easily identifiable attributes that young children understand at an early age. As kindergartners gain more knowledge, they are able to sort and classify objects into a wider variety of attributes such as texture, state of matter, animal type or type of pattern. The language of sorting is important for the development of number sense, so ensure that kindergartners are exposed to concepts such as more, fewer, greater, least and none as they sort and classify.

## Integrate Science

One early science activity on sorting and classifying objects involves living versus nonliving objects. A collection of small plastic toy animals, cars, people, bugs, buildings, plants and rocks along with mats or bowls for sorting is adequate for this activity. Kindergartners also investigate how living creatures move. Provide toy models or pictures of creatures that move in different ways such as frogs that hop, bugs that crawl, horses that walk and snakes that slither for sorting. Another investigation is sorting objects according seasonal categories, such as coats, beach balls, fall leaves and snow boots.

## Possible Materials

Any small objects that can be sorted by various attributes are acceptable for creating a sorting-and-classifying station in a kindergarten classroom. Buttons, rocks, marbles, stickers, paper cutouts, large beads, silk flowers, blocks, old game pieces or small tiles have many attributes that allow students to sort in various ways. Expose kindergartners to the meaning of terms such as shape, color, size and texture before participating in the center. Check object sizes. All objects must be large enough not to be a choking hazard at this age. Alternatively, use snack foods to provide a sorting material. Have students sort dry cereal, fruit gummy snacks or various crackers then eat them as a snack.

## Teacher or Student Categories

Initially, teachers provide kindergartners with the attributes for sorting and classifying, beginning with one attribute and later adding more than one attribute. For example, teachers may ask students to classify objects by shape and size. Because kindergarten students are just beginning to sort and classify, they initially have a limited vocabulary for independently naming the attributes. By the time they are 4 or 5 years old, students can sort by more than one attribute such as color and shape. After practice identifying attributes for sorting, students can begin to sort by self-selected attributes. As students progress through kindergarten, they can sort and classify by self-selecting attributes from a larger vocabulary. They benefit from opportunities to analyze objects such as small rocks and independently determine many attributes by which to sort and classify the rocks.