Count the cubes in the top layer (rows × cubes in a row), then multiply by how many layers tall it is.
unit cubea cube 1 unit on every side
layerone flat level of cubes
solid figurea shape that takes up space
hiddenbehind or under, not seen in the picture
Watch for: Counting only the cubes you can see and missing the ones behind. Counting a cube twice where two faces show. Adding the layers' sizes instead of multiplying.
At home: Build a block with sugar cubes or building bricks and count them. Then guess how many a block twice as tall needs.
Sample sheet and answer key
Luna's Space Adventure
Grade 3 · Building with cubes · OK.3.GM.1.2
NameDate
Astronaut Luna is exploring a far-off corner of space. Solve each problem to help Luna's mission go smoothly!
How many cubes to build it?
Count the cubes in the top layer, then count the layers. Some cubes are hidden behind.
cubes
cubes
cubes
Plan the build
One layer, then how many layers.
A layer 2 cubes long and 3 wide, stacked 4 layers high. How many cubes?
A layer 2 cubes long and 3 wide, stacked 2 layers high. How many cubes?
A layer 3 cubes long and 3 wide, stacked 3 layers high. How many cubes?
Which takes more cubes?
Circle the one built from more cubes.
Grade 3 · Sheet
Luna's Space Adventure
Grade 3 · Building with cubes · OK.3.GM.1.2
Answer key
Astronaut Luna is exploring a far-off corner of space. Solve each problem to help Luna's mission go smoothly!
How many cubes to build it?
Count the cubes in the top layer, then count the layers. Some cubes are hidden behind.
18cubes
8cubes
6cubes
Plan the build
One layer, then how many layers.
A layer 2 cubes long and 3 wide, stacked 4 layers high. How many cubes?24
A layer 2 cubes long and 3 wide, stacked 2 layers high. How many cubes?12
A layer 3 cubes long and 3 wide, stacked 3 layers high. How many cubes?27
Which takes more cubes?
Circle the one built from more cubes.
Answer key
Something wrong with this sheet? A wrong answer, a hard-to-read picture? Report it
New problems every time, three levels (gentle, core and stretch), themes to pick from, a second page if you want one. Each sheet comes with an answer key and a one-page guide for grown-ups.
