This is the first lesson for the unit on surface area and volume of solids. The lesson is designed to reacquaint or teach students some of the key vocabulary of prisms and pyramids while teaching them how to draw the figures. I have found that students are empowered when they learn to draw the figures. MP5 is addressed as students use tools (whether it be protractors or shape templates) to help understand the various prisms and pyramids. It also address MP4, perhaps at a rudimentary level, but student create the models to help solve the problems at hand. So while this addresses 7.G.6 and MP4 AND MP5, students are often very excited when they learn how to draw these figures. This will also help students to visualize 2D representations of prisms and pyramids when drawing nets, finding surface area, or volume.
I’ll start the lesson by posing the essential questions of the lesson: 1) How can you draw a prism? 2) How can you draw a pyramid? 3) What are the similarities and differences between prisms and pyramids? I am not looking for any answers yet (they will be answered soon enough). I am setting the stage so that students know the purpose of the activities to follow. I’ll show the exit ticket questions, so that students know what they should be able to do by the end of the lesson. Then, we’ll go through some important vocabulary for the lesson: prism, pyramid, base, and lateral face. At this point, question number 3 can be addressed. I will post a t-chart to labeled Similarities | Differences and record some responses. Being able to describe the solids accurately is an example of attending to precision (MP6).
Next, I will show students how to do a freehand drawing of a rectangular prism and a rectangular pyramid. I will draw the shape one step at a time. Students will copy one step at a time. I will then make a quick pass through the class to make sure everyone has drawing the shapes correctly. Now, we can address the essential questions. Next students will work on drawing a triangular prism and pyramid. I will ask them to draw each shape one step at a time. I will only draw after seeing that most students have each step down. I insist on one step at a time to mitigate compounding errors. Again, we can address the essential questions and update the t-chart as necessary. I will push students to find more similarities and differences as necessary.
Finally, I will guide the students on drawing regular prisms and pyramids using a protractor. We did some protractor work earlier in the year as an enrichment activity, but I expect to have to remind students on how to properly measure each angle and the length of the sides of the base. I’ll encourage students to be as accurate as possible but it is okay to be off by a degree or two. I had initially considered doing all of these drawings freehand, but I remembered that my students always get excited when they get to use protractors and they need more experience measuring. Before moving on, I’ll ask for any additions to the t-chart. At this point, students should be pretty confident about some answers to the 3 questions.
Now students will draw a few regular prisms and pyramids using a protractor and a straight edge. I’ve included a template or worksheet that could be used for these drawings, but notebook paper, or even better, scratch paper with one clean side would work. Either way, this part of the lesson is set up so that students will have a side-by-side comparison of prisms and pyramids that share the same base. This allows for more evidence to support our answers to the essential questions. During this part of the lesson, I will walk around to give support to students who are having difficulty using their tools. I will encourage students to use a dictionary if they are unsure of how many sides to draw for a pentagon or hexagon. I will tell students to draw as neatly as possible because I’d like plenty of examples to post in the room. Students may use markers or colored pencils once they have completed each drawing accurately – I let them know!