Counting is a main area of focus for math at this level, as it is the basis for understanding the number system. Many of the counting activities in kindergarten build a bridge to the operations of addition and subtraction. Students are provided with repeated experiences of counting sets of objects and matching and making sets of a given size. They work on activities that involve seeing and describing a given quantity in groups. They are also asked to decompose quantities and to find one or more combinations of a quantity. Students use story problems and play a variety of games to model the operations of addition and subtraction. Students have many opportunities to determine how objects are the same and different and sort them into groups according to their attributes. They also construct, describe, extend and determine what comes next in repeating patterns. Students are introduced to length and linear measurement through direct comparison and the use of non-standard units. They also build on their firsthand knowledge of shapes to further develop their spatial sense and deepen their understanding of the two- and three-dimensional world, and explore the idea that shapes can be combined or subdivided to make other shapes. Students gather and record data through multiple forms (graphs, tallies, tables).