
Block Builder
Multiplication is a rectangle: the number of rows multiplied by the number of columns equals the area, so every times-table product can be built and counted as an array.

What your child will figure out
- Build a requested multiplication array by resizing its rows and columns, then verify the product by skip-counting equal rows.
- Read the product represented by a completed rectangular array and connect the factors to its two dimensions.
- Find a missing factor by holding one array dimension fixed and resizing the other until the target area is reached.
- Transform arrays by turning, resizing, doubling, and matching equivalent areas; connect missing factors to division and develop flexible fluency across factors 1–12.
The levels
- Plan a 3 × 4 floor
Predict 12, build three rows of four, skip-count 4, 8, 12, and explain that rows × columns counts every square.
- Read the rectangle
Name the product shown by a completed 4 × 6 array and verify 24 by counting equal rows.
- Finish the 42-tile wall
Solve 6 × ? = 42 by keeping six columns fixed and resizing the array to seven rows.
- Add one whole row
Transfer the rectangle model from 5 × 8 = 40 to 6 × 8 = 48 and explain why one new row adds eight squares.
- Turn the window wall
Rebuild 4 × 9 as 9 × 4 and establish that turning an array preserves its 36 squares.
- Remove two seat rows
Change 8 × 7 = 56 to 6 × 7 = 42 by removing two complete groups of seven.
- Complete the 72-panel roof
Solve 9 × ? = 72 by holding nine rows fixed and finding the eight-panel width.
- Raise a square tower
Build and verify the square fact 11 × 11 = 121.
- Double the banner
Double 4 × 12 = 48 to 8 × 12 = 96 and connect doubling one factor with doubling the product.
- Rebuild the same courtyard
Show that 6 × 10 and 5 × 12 are equivalent arrays with area 60.
- Reverse the 96-block plan
Connect division and missing factors by solving 96 ÷ 12 = 8 as an 8 × 12 array.
- Complete the master grid
Integrate prediction, two-axis building, skip-counting, and explanation in the 12 × 12 = 144 capstone.
Ready when they are.
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