Geometry in the News

by Kathryn Hindt

Fort Bend Independent School District

Course:
Mathematics / Title of Unit:
Geometry / Title of Lesson:
Geometry in the News
Grade Level:
3rd / Time Frame:
2 90-minute periods
Description
Students will use the newspaper to locate examples of geometric figures in real life. They will cut out pictures, mount them on paper, and include a definition of the shapes they find.
TEKS Objectives
3.8 Identify, classify, and describe two- and three-dimensional geometric figures by their attributes; compare two-dimensional figures, three-dimensional figures, or both by their attributes using formal geometry vocabulary
3.9A Identify congruent two-dimensional figures
3.9C Identify lines of symmetry in two-dimensional geometric figures
Teacher to Teacher Notes
Preparation: Cut apart geometry vocabulary words and pictures (pp. 7-17), back on colored paper, and laminate. Use masking or magnetic tape to arrange the images and words on wall or board; words on one side of the board and images on the other. Run off geometry term cards (pp. 3-6) on cardstock so that pictures are one side of the paper and the corresponding definitions are on the opposite side. (These cards can also be run on only one side of cardstock to use as a memory or concentration game.)
Students will work in partnerships for this activity.
**IMPORTANT: Make sure to demonstrate how to unfold and refold newspaper before beginning the activity!! Make clear your expectations for the location and look of the newspapers when you get them back.

Materials

·  drawings of geometric shapes and name plates of their names (pp. 7-17 of lesson)
·  models of 3 dimensional figures
·  4.5” x 6” sheets of manila or construction paper.
·  geometry cards (pp. 3-6 of lesson) /

Resources & Technology

http://www.chron.com/cie/hc.html
http://www.chron.com/
http://www.fotomat.com/home/KHINDT/1M4C8C0C0MEBHH.EZP
(digital pix of activity)
Procedures/Activities
Engage: Draw students’ attention to the board or wall on which geometric figures are posted. Ask if they see any similarities or differences in the figures. Ask if they see ways we could classify the figures according to their attributes. Elicit that some figures are flat and some are space figures.
Explain: Introduce the terms 2-dimensional and 3-dimensional. Discuss what students already know about those terms. Explain and show that 2 dimensional figures have only 2 dimensions to measure or 2 measurements, a length and a width. Then explain and show that 3-dimensional figures actually have those 2 measurements plus height. That’s where the 3 comes from in 3-d. Show how the base of the 3-d figure has length and width and “grew up” from there. The 3 “d’s” or 3 dimensions or 3 measurements are length, width, and height. Place the two headings “2-dimensional” and “3-dimensional” on separate sides of the board. Rearrange the geometric figures under the correct heading or select student volunteers to do so.
Next, in random order post the names of the geometric figures on the board with masking or magnetic tape. Select student volunteers to take one term and match it to the corresponding geometric figure on the board. Have them place the term underneath the figure. Continue until all figures have been named and discussed. Review terminology such as edges, faces, vertices, base, length, width, height, sides, angles, symmetry, and congruence along the way. Pass around models of 3 dimensional figures when appropriate so students can touch the edges, faces, vertices, etc.
Explore: Assign student partnerships one card at a time (from pp. 4-7) and tell them to search through the newspaper to find pictures of each shape. Instruct them to glue the picture on a sheet of 4.5 x 6 (or other) manila or construction paper, write the word, and give a definition of the word (See link to digital photos for examples to show class). As student pairs complete a card, hand them another one until each pair has completed at least 3. Some terms will be duplicated. Display the work on a wall.
Sum it up: What is one way to classify geometric figures? (2-d and 3-d)
What does the d stand for? (dimension)
What does dimension mean? (measurement)
What are the 2 d’s in 2-d? (length and width) in 3-d? (add height)
Other questions such as “What is the name for a six-sided figure?” and “How many faces does a cube have?” could be reviewed at this time.
Extend: Assign students to look for shapes on their way home, running errands with their parents, or in any other of their after school activities. Have them keep a log or take pictures if they can of their sightings and discuss their findings as a group on a designated day.

click here to see photos of children using the newspaper for this activity:

http://www.fotomat.com/home/KHINDT/1M4C8C0C0MEBHH.EZP

triangle /
hexagon
rectangle /
octagon
square /
circle
pentagon /
triangular prism
A polygon with 6 sides / A polygon with 3 sides
A polygon with 8 sides / A polygon with 4 sides. Opposite sides are congruent and all 4 angles are congruent.
A plane figure with no sides / A polygon with 4 sides. All the sides and angles are congruent.
A 3-dimensional figure with:
5 faces
6 vertices
9 edges / A polygon with 5 sides
rectangular prism /
cone
cube /
sphere
square pyramid /
congruent
cylinder /
Line of symmetry
A 3 dimensional figure with:
1 flat circular face
A curved surface / A 3 dimensional figure with:
6 rectangular faces
8 vertices
12 edges
A 3 dimensional figure with:
No faces
A curved surface / A 3 dimensional figure with:
6 square faces
8 vertices
12 edges
Same shape and same size / A pyramid with a square base &:
5 faces
5 vertices
8 edges
The line at which a shape can be folded so that its two halves match exactly / A 3 dimensional figure with:
2 flat circular faces
A curved surface

2

triangles squares

rectangles hexagon

triangular prism cone

rectangular prism cube

octagon cylinder

square pyramid sphere

pentagon circle

2 dimensional

3 dimensional

2

2