In this lesson, students will develop strategies for finding the area of rectangles with whole-number side lengths by tiling it, and show that the area is the same as would be found by multiplying the side lengths. Keywords: area, square units, unit squares, rectangle, tiling, tiles, side lengths, multiplication, multiplying. In this unit on area, students explore geometric measurement by becoming "Area Architects" in order to learn the concepts of area and relate area to multiplication and addition. Students need to understand that multiplication can be modeled using arrays. Students need to understand that arrays represent multiplication as 𝑥 number of rows with 𝑥 number of tiles in each row.