# Pretzel and marshmallow solid geometric figures are assembled here

Subject:

Math

3

Title – Pretzel and Marshmallow Solids
By – Susanne Cauley
Primary Subject – Math

Concept / Topic To Teach:

• Solid Figures

• NC Standard Course of Study – 3rd Grade Math
Objective 3.01 – Use appropriate vocabulary to compare and describe three-dimensional figures.

General Goal(s):

• Describe a solid figure by telling about its parts.

Specific Objectives:

• Classify space figures and identify the faces, edges and corners.

Required Materials:

• set of solid figures
• real-world examples of solid figures
• large marshmallows
• pretzel sticks
• math notebooks

• Review names of solid figures by holding up the following items:
• can of soup
• baseball
• stick of butter
• jack-in-the-box (or other available solid objects)

Step-By-Step Procedures:

1. Define face, edge and corner (also know as vertex or vertices). Face
: flat surfaces created by line segments

Edge

: line segment where two faces meet

Corner or Vertex

: where three or more edges meet
2. Create a table together. (Teacher models and students copy and record data in math notebooks.)
 Solid Figure Faces Edges Corners Sphere 0 0 0 Cube 6 12 8 Rectangular Prism 6 12 8 Pyramid 5 8 5 Cone 0 0 0 Cylinder 0 0 0
3. Show children that pyramids can have squares for a base or triangles for a base.

Plan For Independent Practice:

1. Pass out the pretzel sticks and marshmallows.
2. Instruct students to build a cube using the pretzel sticks as the line segments and marshmallows as the corners. (I usually just pass out enough extras so students can eat a few to start with, then they will focus more on the work instead of constantly asking when they can eat!)
3. Once a cube has been constructed, instruct students to build a pyramid. They can build one with a square base or a triangle base or both as time allows.

Closure (Reflect Anticipatory Set):

• Do your pretzel marshmallow structures have the proper number of faces, corners and edges? Compare them to your chart.
• Can you build any other solid figures with these same pretzel sticks and marshmallows? Why not?

Assessment Based On Objectives:

1. How many marshmallows would you need to build 2 cubes?
2. How many pretzel sticks would you need to make 3 pyramids?

Adaptations (For Students With Learning Disabilities):

• Work with a partner to construct pretzel marshmallow solids.