Kindergarten · Number
Change in Quantity to 10
Before students meet the '+' symbol, they need to understand what adding and subtracting actually do: they change a quantity. Build-and-change tasks are the most powerful way to develop this understanding. 'Start with 4 cubes. Change your collection to show 6. How did you do it?' requires students to reason about the difference — to think 'I need 2 more' — without an equation in sight.
LESSON VIDEO
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Lesson video
A short walkthrough to play in class or assign for flipped/at-home viewing.
WHAT STUDENTS WILL LEARN
✓Describe and model adding 1 or 2 to a set using concrete materials
✓Describe and model removing 1 or 2 from a set using concrete materials
✓Use build-and-change tasks: 'Start with 4. Change it to 7. What did you do?'
✓Use language of change: more, fewer, added, took away, now there are
✓Connect change in quantity to the beginning state and the result