To determine the surface area of a geometric solid, students must be able to visualize three-dimensional objects from two-dimensional drawings. This pre-requisite skill can be practiced in the classroom using manipulatives.

• Have students put together 'nets' to envision and understand how a 2-dimensional shape can be folded to create a 3-dimensional object. The figure below can be cut out, the four squares in a row folded to form a box, and the upper and lower squares form the top and bottom, respectively. This demonstrates how a 'net' can be used to form a 3-dimensional shape. This will help students see the connection between 2-dimensional drawings and 3-dimensional objects.

  

• From the net, demonstrate:
  - The number of faces in the rectangular prism. [6]
  - What type of polygon the faces are. [Rectangles]
  - Which of the faces are congruent. [The ones opposite each other in the prism]
• Ask students can bring common rectangular prisms (tissue boxes, cereal boxes, etc.) from home. With scissors, cut along the edges (fold lines) to turn the three-dimensional prisms into two-dimensional figures. Determine the surface area of the prism by finding the areas of the faces of the prism.