Activity: To make, describe and determine the surface area of composite 3-D objects. (Grade 9 Math)

General Outcome:

Describe the characteristics of 3-D objects and 2-D shapes, and analyze the relationships among them.

Specific Outcome:

Determine the surface area of composite 3-D objects to solve problems.


Task 1: In a group of 2 or 3 students, your will create a composite surface area question using graphics on PowerPoint.  You will then answer the question.

a)  Choose two of the following shapes (cube, rectangular prism, triangular prism or cylinder)

b)  On PowerPoint you will create 3 slides.  Slide #1 will be a 3-D graphic of each shape separated.

c)  Slide #2 will show the composite shape.

c)  Slide #3 will show all 2-D faces for each shape in an organized manner highlighting  area of overlap.

d)  Label measurements on all three slides (length, width, height, radius or diameter)

e)  Find the area of each face and total surface area of composite 3-D shape.

f)  Show all calculations and final answer on paper.

g)  You will submit the entire powerpoint to teacher along with paper calculations

h)  You will submit slide #2 separately,  this will be the composite surface area question you will share with other groups.

Part 2:  In the same group you will pose the same composite area question, this time using audio.

a)  Using a program called Audacity, you will pose your surface area question.

b)  Describe the composite shape and give all necessary measurements.

c)  Be sure to carefully describe and give measurements for the area of overlap.

Part 3:  Working on questions from other groups.

a)  You will be provided with three PowerPoint questions and use the visuals to help solve each problem.

b)  You will be provided with three audio questions from Audacity and are required to solve each problem with the audio descriptions.


Resources to use: 

A) PowerPoint

Video to help with making 3-D graphics:


B)  Audacity

Video to help with voice recording:



Since I am currently working on surface area of composite shapes with my grade 9s, I was trying to come up with an activity that I could could put to work in the classroom immediately.  Students typically find it hard to look at a 2-D drawing of a 3-D shape and see all of the faces.  I do an activity where students use nets of prisms and cylinders to create the shapes, fold them together, find area of overlap and then find total surface area.  This definitely helps with area of overlap, they can physically put the shapes together and also look at them separately.  I thought if the students could build the shapes using graphics and manipulate them on a computer, this would be an equally valid activity.

After experiencing a number of different programs for making graphics, I decided on using PowerPoint.  The reason was the ease of making  3-D shapes and being able to manipulate them without many problems.  Word was totally frustrating when it came to moving multiple shapes around the screen.  I found another program called SketchUp, which at first seemed very promising, however there was many functions and it seemed too complicated to learn in a short period of time.  I want this lesson to last a maximum of 3 class periods.

Using graphics is a great way to stimulate the visual learners in the class where it is important for them be able to picture what they are using in their heads.  Clark and Lyons talk about for learning to occur all instructional methods, including graphics must support several critical psychological events.  The two I see at work in this lesson are building new or expanding mental models in memory and managing mental loads to free resources for learning.  (Clark, R.C & Lyons, C., 2010)

For the second part of my activity I thought it would be interesting for the students to make an audio recording where they have to describe a process in great detail as well as listen to a recording and try to answer a question.  This is not a method I would use very often so I am interested to see how it will work.  Having students answer surface area question that are so visual by nature with purely auditory clues seemed like good way to reinforce the learning for all students while at the same time appealing to those students who were auditory learners.  Sometimes I forget that there are students who have an easier time storing information by the way it sounds and don’t necessarily always need a visual medium. Research has shown us that the brain processes information using two channels—visual and auditory. By taking advantage of the auditory processing capability and technology-based tools, we can dramatically enhance student learning through auditory instruction. (Brady-Myerov, 2017)  

Part 3 of my activity involves the students answering other groups questions.  The groups will answer some questions with graphics and some with only auditory clues.  I will be doing this activity after spring break and I am interested to see how it will work and am hopeful that it will be a rich learning task.



Clark, R.C & Lyons, C. (2010). Three views of instructional visuals, In Graphics for Learning: Proven Guidelines for Planning, Designing and Evaluating Visuals in Training Materials. San Francisco: Pfeiffer, 15-28.

Brady-Myerov, Monica:


1 Comment on Creating a Multimedia Enhanced Student Activity

  1. mpehkonen says:

    Hi Steve,

    I agree with you when you say that it is sometimes difficult for students to visualize 2D views on 3D shapes, especially composite shapes. I think the graphics they will create in PowerPoint can definitely help in this regard. Your instructions for the task are nice and clear. I am going to start working on my final graphic and will look into PowerPoint and SketchUp. I will also look into 3D shapes in Word as I had success with Word however, I was looking at 2D shapes. Great job Steve.


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