[Free Registration/Login Required] In this lesson, students will connect the concepts of counting each square unit and multiplying the side lengths to compute the area of a rectangle. They will extend this knowledge by computing a side length when given only the area and the other side length. The lesson includes detailed steps, accommodations for students, assessment ideas, and guided instruction questions. Extra resources are available including ideas for using Geoboards to teach this concept. CCSS.Math.Content.3.MD.C.7.a Find the area of a rectangle with whole-number side lengths by tiling it