Surface Area of Prisms and Pyramids Lesson Plan

Warm-up

Start out the lesson by sharing slide one of the teacher slideshow and ask students to write down a bunch of real life or household items they can come up with that are prisms and pyramids.

Give students a few minutes to jot down their ideas and then have them share with a partner. Once the discussion comes to an end, have students share with the class. Students may share tissue boxes, cereal boxes, tents, dice, storage boxes, pyramids in Egypt, etc. Write these on the board for all students to see. Share any other examples that students did not get to share.

Explore the concept of surface area

Present a picture of the box and ask students how would they figure out how much cardboard was used to make this box.

Students are likely to come up with interesting ideas for finding how much cardboard was used. Some might want to measure the edges of the box. Some might suggest that we open up the box and measure the sides of each face - they are likely to make a connection to the idea of nets that learned in the earlier class.

Show them how the box looks like when it is opened. Of course there are flaps that are used to tuck in the edges. Tell them that for now we will ignore them or measure them separately. Introduce the concept of surface area and tell that today we will find the surface area of prism and pyramids.   

Introduction to the activity

Explain to students that we’re going to find the surface area of some of these objects. We’ll use tissue boxes, cereal boxes, toblerone candy bars, and a square pyramid. We’ll unfold the boxes to be able to see the shapes in `2D`. Then we’ll find the area of each part to find the total surface area of the object!

Surface area of household objects activity

Hand out the Surface Area of Prisms and Pyramids Activity Worksheet, rulers, scissors, and one tissue box, cereal box, toblerone box, and square pyramid to each group of four students. 

Remind students of the steps for finding surface area:

• Step `1`: Number each face of the objects
• Step `2`: Measure the dimensions of each face
  • Remind them that with triangles, they will need the height and the base of the triangle
  • They should stick to one unit while measuring the dimensions
  • You might have to do a demonstration of how to measure using the ruler (starting at `0` and not at `1`, etc)
• Step `3`: Find the area of each face (be careful about what formula to use based on the shape!)
• Step `4`: Add all of the areas together

The first part of the hand-out gives them the steps and asks them to describe and name the object and make a drawing of the object before and after opening it.

The second part is where they do the actual measurements and calculations. There is an organized sheet where they can record their measurements and the areas.

Class presentation

Invite a few groups to present their work. Ask them to talk about what kind of object they were working with and how they found the area. Ask them to describe some of the difficulties they faced when doing this activity.

You could ask students what kind of people would want to know about how much cardboard is needed to make these objects. Ask them to estimate what it might cost to make the packaging that they were working with.