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.
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.
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).