​​Be sure to read the teacher guide prior to running the task. When you’re ready to run the task, use the tabs at the top of the page to navigate through the lesson.

Intentionality…

The purpose of the Day 2 activities is to reinforce key concepts from Day 1. Students will engage in a string of related problems through a math talk and will have an opportunity to complete purposeful practice. The math talk and purposeful practice serve to develop a deeper understanding of the following big ideas.

Some of the big ideas that may emerge today include:

• Understanding hierarchical inclusion allows for flexible composing and decomposing of numbers
• Numbers can be decomposed by separating a whole into two or more parts
• Addition names the whole in terms of the parts 
• Different addition situations will elicit different strategies 
• Number relationships provide the foundation for strategies to help students remember basic facts
• Models can be used to connect concrete to abstract 

Before starting this unit, students should be familiar with:

• Facts of 10 ( e.g., 6 + 4 = 10, 10 – 4 = 6)
• Flexibility when decomposing numbers (e.g., 13 can be decomposed into 10 and 3, but also 9 and 4, 8 and 5, etc)

The Up and Over Ten strategy which can be explored in the Bowling Pins Unit.