Lesson objective: Count numbers in sequence up to 20, starting at 1.

This lesson helps to build a procedural skill with counting numbers in order up to 20. Ten frames are used here because they support the development of a visual image to support the numbers students are rote counting. This work develops students' understanding that numbers exist in a sequence that does not change, and they can be counted.

Students engage in Mathematical Practice 6 (Attend to precision) as they work on counting precisely and in order.

**Key vocabulary:**

- counting
- eight
- eighteen
- eleven
- fifteen
- five
- four
- fourteen
- nine
- nineteen
- numbers
- one
- seven
- seventeen
- six
- sixteen
- ten
- thirteen
- three
- twelve
- twenty
- two