Module 6, Topic C introduces the idea of a slice (or cross-section) of a three-dimensional figure. Students explore the two-dimensional figures that result from taking slices of right rectangular prisms and right rectangular pyramids parallel to the base, parallel to a lateral face, and slices that are not parallel to the base nor lateral face, but are skewed slices (7.G.A.3). The goal of the first three lessons is to get students to consider three-dimensional figures from a new perspective. One way students do this is by experimenting with an interactive website that requires students to choose how to position a three-dimensional figure so that a slice yields a particular result (e.g., how a cube should be sliced to get a pentagonal cross-section).

Content Standard(s):

Mathematics MA2019 (2019) Grade: 7

19. Describe the two-dimensional figures created by slicing three-dimensional figures into plane sections.

Unpacked Content

Evidence Of Student Attainment:

Students:

Describe the two-dimensional figures that result from slicing three-dimensional figures, as in plane sections of right rectangular prisms and right rectangular pyramids.

Teacher Vocabulary:

Two-dimensional figures

Three-dimensional solids

plane sections

Knowledge:

Students know:

the difference between a two-dimensional and three-dimensional figure.

The names and properties of two-dimensional shapes.

The names and properties of three-dimensional solids.

Skills:

Students are able to:

Discover two-dimensional shapes from slicing three-dimensional figures. For example, students might slice a clay rectangular prism from different perspectives to see what two-dimensional shapes occur from each slice.

Understanding:

Students understand that:

slicing he prism from different planes may provide a different two-dimensional shape.

There are specific two-dimensional shapes resulting from slicing a three-dimensional figure.

Diverse Learning Needs:

Essential Skills:

Learning Objectives: M.7.19.1: Define two-dimensional figure, three-dimensional figure, and plane section.
M.7.19.2: List attributes of three-dimensional figures.
M.7.19.3: List attributes of two-dimensional figures.
M.7.19.4: Describe the relationship between two- and three-dimensional figures.
M.7.19.5: Recognize symmetry.

Prior Knowledge Skills:

Identify that shapes in different categories (e.g., rhombuses, rectangles, and others) may share attributes (e.g., having four sides), and that the shared attributes can define a larger category (e.g., quadrilaterals).

Recognize and draw shapes having specified attributes such as a given number of angles or a given number of equal faces.

Identify triangles, quadrilaterals, pentagons, hexagons, heptagons, and octagons based on the number of sides, angles, and vertices.

Define three-dimensional figures, surface area, and nets.

Select and create a three-dimensional figure using manipulatives.

Identify three-dimensional figures.

Alabama Alternate Achievement Standards

AAS Standard: M.AAS.7.19 Match two similar geometric shapes that are proportional in size and orientation.

Tags:

crosssection, right Rectangular prisms, right Rectangular pyramids, slice, threedimensional, twodimensional