Lesson objective: Understand that the last number name said represents all of the objects that have been counted so far.

Students bring prior knowledge of rote counting to 10 from K.CC.1. This prior knowledge is extended to cardinality as students learn that number names represent collections of objects. A conceptual challenge students may encounter is believing that numbers are names for individual objects rather than collections.

The concept is developed through work with counters (cubes), which help students consider different sized sets and the number names that name those sets.

This work helps students deepen their understanding of number because sets of objects can be counted and represented by number names.

Students engage in Mathematical Practice 6 (Attend to precision) as they apply counting strategies to naming sets of objects.

**Key vocabulary:**

**Special materials needed:**

- cubes (or some other counters)