Story about combining any amounts and equal amounts

Comparing to find the difference:

Jessica is 8, Bradlee 6. Jessica is how much older than Bradlee?

Using snap cubes for years, Jessica’s age would be shown with an 8-stick, Bradlee’s with a 6-stick. To show the difference between their ages, a 2-stick would be snapped off or “just” separated from the 8-stick.

Subtraction as “Just” Separating

Take away:

Eight birds in a tree, six flew away. How many still in the tree?

Using snap cubes for birds, a 6-stick would be removed or “just” separated from an 8-stick to show the birds still in the tree.

Counters showing adding as combining any amounts
Counters showing counting on model for addition

Counting on:

Six apples and two more. Now how many apples?

Using snap cubes for apples, one cube and then another would be joined or “just” combined with a 6-stick to show two more apples in succession.

Counters showing take away model for subtraction
Counters showing comparing find the difference model for subtraction

Multiplication as Combining “Neatly” (by 2s, 3s, 4s…)

Grouping or repeated addition:

Four cans of tennis balls, three balls to a can. How many tennis balls?

Using snap cubes for tennis balls, a 3-stick would show the number of tennis balls in a can. To show the number of tennis balls in four cans, four 3-sticks would be joined or combined “neatly” (by 3s).

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