Materials: one rectangular prism, cube, sphere, cone, cylinder, and also pyramid for each group of students

Preparation: distribute solid figures to teams of students.

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Prerequisite an abilities and Background: college student should have the ability to recognize and also name solid figures.

Ask: Which solid numbers have deals with that are polygons? (rectangular prism, cube, and pyramid)Say: Put the various other solid numbers aside because that now.Ask: Which solid number has encounters that are rectangles? (rectangular prism)Say: Count the number of faces a rectangular prism has. Mark an X on each confront as friend count.Copy this table on the board as students space working.

Solid Figure

Number the Faces

Number that Edges

Number of Vertices

 Solid figure Rectangular Prism

Ask: How numerous faces does a rectangular prism have? (6) document 6 top top the table.Say: The heat segment whereby two faces meet is one edge. Counting the variety of edges a rectangle-shaped prism has. Mark one X on each edge as you count.Ask: How many edges go a rectangular prism have? (12) document 12 top top the table.Say: The allude where edges satisfy is a vertex. Counting the number of vertices a rectangular prism has. Mark one X on each vertex together you count.Ask: How countless vertices go a rectangular prism have? (8) document 8 ~ above the table.Have students find the number of faces, edges, and also vertices of a cube and a pyramid. Record the answers in the table.

Solid Figure

Number the Faces

Number that Edges

Number the Vertices

 Solid number Rectangular Prism number of Faces 6 number of Edges 12 number of Vertices 8 Solid number Cube variety of Faces 6 number of Edges 12 variety of Vertices 8 Solid figure Pyramid variety of Faces 5 number of Edges 8 variety of Vertices 5

Ask: Why perform you think that a rectangular prism and a cube have actually the same number of faces, edges, and vertices?Lead students come realize the the deals with of a rectangle-shaped prism and also a cube are all rectangles, but in the instance of the cube, the rectangles are squares. A cube is a special rectangular prism.Say: Take the end your solid numbers that have curved surfaces. Look at the sphere.Ask: Does a round have any kind of edges or vertices? (no) Why not?Students have to realize that a sphere has no faces, so that can"t have any kind of edges or vertices.Say: Look at the cone.Ask: Does a cone have any edges? (no) Why not?Students should realize the a cone has only one face, and you need much more than one confront to kind an edge.Ask: Does a cone have any kind of vertices?Lead student to view that a cone has actually no edges, yet the suggest where the surface of the cone ends is called the vertex of the cone.Say: Look at the cylinder.Ask: Does a cylinder have any edges or vertices? (no) Why not?Students must realize that although a cylinder has two faces, the encounters don"t meet, so there space no edge or vertices.

Wrap-Up and Assessment HintsEncourage students come explore much more attributes of continual solid figures. Ask questions such as the following: Which solid numbers have opposite faces that space parallel? (rectangular prism, cube, cylinder) Which solid figures have opposite deals with that room congruent? (rectangular prism, cube, cylinder, pyramid) Which solid number has every congruent faces? (cube) v questioning methods such as these, girlfriend will have the ability to judge her students" expertise of hard figures.

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