Chris' garden dilemma
This mathematics unit contains a curriculum‐embedded Common Core–aligned task and instructional supports. The task is embedded in a 3–4 week unit on solving real‐world problems to reinforce the strategies of tiling, multiplication, addition, and area models to calculate the perimeter and area of polygons. This unit falls approximately between January and February in 3rd grade. At this point in 3rd grade students should have done substantial work with multiplication before beginning this unit. In 2nd grade, students should have received instruction in the following key concepts: repeated addition strategies, work with arrays to build the foundation for multiplication, and using appropriate tools to measure objects using standard units of measure. By 3rd grade, students develop an understanding of the structure of rectangular arrays and area. Also, students will recognize area as an attribute of two‐dimensional regions. They measure the area of a shape by finding the total number of same‐ sized units of area required to cover the shape without gaps or overlaps, a square with sides of unit length being the standard unit of measuring area. Students connect area to multiplication and justify using multiplication to determine the area of a polygon. In 4th grade, students will apply their understanding of models for multiplication. In addition, students will apply formulas for rectangles to find the perimeter and area in solving real-world problems. This task requires students to use multiplication, addition, tiling, and area models to determine perimeter and area. In addition, students will need to demonstrate and explain their reasoning of strategies used to solve the task.