MULTIPLICATION & DIVISION 4: DIVIDE INTO ARRAYS OF EQUAL ROWS,
AND BARS, DESCRIBE USING MULTIPLICATION BY PARTITIONING AND
SUBITISING AND COMMUTATIVITY
MEASUREMENT 19: MEASURE & COMPARE AREAS USING UNIFORM INFORMAL SQUARE UNITS IN ARRAYS

Dividing into an array allows students to identify whether groups are equal. Arrays also allow students to begin to partition their division and multiplication to make it simpler, for example, an array of 3 rows of 5 may be partitioned into 2 rows of 5 (10) and 1 row of 5 (5), making it simpler to work out the total is 15.
Dividing into bars and describing using multiplication is an effective way to transition into multiplicative thinking in Year 3 onwards, and is touched on in Year 2.
When we measure area, we use squares arranged in an array.

NB: The Teaching Resources have been linked below as a complete document containing all Elements (button 1), buttons 2 and 3 are the individual Teaching Plans, buttons 4 and 5 are the Problem Solving PowerPoints. The remaining buttons are the Videos.