Making rectangular arrays with tiles is a great visual way to have students understand multiplication as repeated addition. And since we’re making arrays anyway, why not tie in square numbers. A square number is: 1) A number that can be expressed as the product of the same two numbers. 2) The product of a number multiplied by itself. When making rectangluar arrays, square nuumbers (1, 4, 9, 16…) always make a square.

Besides, there are some very neat patterns that occur in square numbers and I want my students to see them. Looking for patterns in numbers shows students that there really is rhyme and reason to math. When kids know that math makes sense, they are more likely to persist at understanding it.

These examples are from fourth grade. For my high students, we talk about exponential notation then they record the appropriate notation for each square number.

CCSS: 3.OA.1; 3.OA.9
TEKS 4th grade: NO4C