This Instructional Activity is a part of the Lesson 17, Unit 3, Grade 6. This activity is comprised of two major parts: finding the total wall area to be painted and estimating needed supplies and associated costs. Students use a floor plan of a bedroom and a list of its features and measurements to calculate the room's total wall area. They then use the square footage to make purchasing decisions and estimate costs. Because of the variations in the bedroom's walls and features, keeping track of the shapes to be included or excluded from the area calculation may be challenging to students.