Creating 3-D Objects: Teacher Notes

Independent Learning — Students work independently designing appropriate products for the problems provided.

Students will begin to identify the properties of three-dimensional objects (points, edges, faces) and then construct three-dimensional objects.

Procedure:

Student’s Role:

Students are to design solids using marshmallows and toothpicks or pipe cleaners. The marshmallows are the points of the solid and the toothpicks are the edges. They can create their own solids after they try to make at least three different solids from the list below.

Create a solid with square and rectangle faces.

Create a solid with triangle faces

Create a solid with circle and triangle faces

Create a solid with triangle and square faces

Create a solid joining two or more solids

Students should have at least three solids be the time they are done. They can eat the rest of the marshmallows then. Students will also create a name tag for the solids they created to be hung on a mobile. The mobile will be made by the teacher when all the solids are done.

Teacher’s Role:

Teacher conducts performance assessment of students to see whether they are creating solids. Teacher asks questions like how many points, edges, faces do the solids have.

Teacher creates a mobile of the solids using the coat hangers and piper cleaners.
Adaptation(s)/Extension(s):

Students can just try to make solids exploring them rather than following instructions.
Tell students to start out be making a shape and then stick some toothpicks in the marshmallows and see what they can make from there so they get the idea of what a solid is.

Saskatchewan Education. (1992). Mathematics: A curriculum for the elementary level. Regina, SK: Author.

Performance assessment — Teacher observes if students are making solids and trying the problems. Teacher asks questions like "How many points (faces, edges) does your solid have?" to check for terminology and understanding. Refer to performance assessment form to go along with activity.

Reflection:

I conducted this activity in my geometry unit during my pre-internship. The students loved this activity. I thought they might just start eating the marshmallows but they did not. I told them I wanted them to eat the marshmallows but they had to have at least three solids made by the end of the class. I think because I said they could eat them there were a lot of issues and concerns that I avoided and it was not on the minds of the students so they could be focused on the task. Most of them forgot to eat the marshmallows as they were creating.

I asked students questions like how many points, edges, and faces their solids had. They were able to tell me easily. A couple students said it was easy because they just had to count the marshmallows. This is giving them the idea of a corner in a visual way for later recognition for solids.

Students were also learning about structural design. Some were learning that things would not stand together unless they supported them. Many of these designs are ones we use in our everyday world to build things; the solids that we live in. This is a good place to bring in ideas of structural support in the real world to coincide with the marshmallow building.

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