Lesson 2

The purpose of this lesson is for students to count and compare collections of up to 20 objects.

This lesson is optional because the standards do not require students to compare groups of objects or written numbers beyond 10. As students represent and compare larger collections, organizing the objects and representations becomes more important to help students keep track. Give students access to 10-frames to help them organize their collections if they choose.

Collections can be created from classroom objects such as connecting cubes, two-color counters, pattern blocks, or buttons. Students can also bring in collections of objects to count from home.

If students need additional support with the concepts in this lesson, refer back to Unit 6, Section A in the curriculum materials.

• Each student needs a collection of 11–20 objects.

• Students need their collection of objects and representation from the previous activity.

• Gather materials from:
  • Less, Same, More
  • Math Fingers
  • Tower Build
  • Math Stories
  • Which One

As students worked together today, where did you see evidence of the mathematical community established over the course of the school year?