What is a Clarifying Lesson?
A model lesson teachers can implement in their classroom. Clarifying Lessons combine multiple TEKS statements and may use several Clarifying Activities in one lesson. Clarifying Lessons help to answer the question "What does a complete lesson look like that addresses a set of related TEKS statements, and how can these TEKS statements be connected to other parts of the TEKS?"
TEKS Addressed in This Lesson
Geometry and spatial reasoning: 5.7A, B; 5.8A, B
Underlying processes and mathematical tools: 5.14A, D; 5.15A, B; 5.16A, B
Materials
- overhead projector and overhead pattern blocks
- tagboard
- pens and markers
- tape
- scissors
- quilt or wallpaper samples (optional)
Lesson Resources
Giganti, Jr., P., and Cittadino, M. J. The art of tessellation, Arithmetic Teacher, (March, 1990), NCTM.
Related Resources
Books about Islamic art, M. C. Escher, and Leonardo da Vinci
OLD Resources. The resources on this page have NOT yet been updated to align with the revised elementary mathematics TEKS. These revised TEKS were adopted by the Texas State Board of Education in 2005, with full implementation scheduled for 2006–07. These resources align with the original TEKS that were adopted in 1998 and should be used as a starting point only.
Clarifying Lessons
Grade 5: Testing for Tessellations
Lesson Overview
Students cover the plane with polygons (and other shapes) to create tesselations.
Mathematics Overview
Students use formal geometric language to describe polygons (and other shapes) that will tessellate the plane and those that will not. Students make generalizations about the characteristics of a polygon (or other shape) that will tessellate the plane and identify the transformations used to create the congruent images that form the tessellations.
Set-up (to set the stage and motivate the students to participate)
- Show designs of M. C. Escher and ask students to discuss what they
notice. Ask students if they have seen other "patterns that cover
the plane" in their environment (e.g., bricks on a patio, certain
wallpapers, tiles in the bathroom and kitchen). (5.14A)
- Tell students
that the repeated use of simple, closed curves (like rectangles or
triangles) to completely cover a plane without gaps or overlapping
is called a tessellation. (5.15B)
- Give students several of one
shape from the pattern blocks. Have students explore to see how they
can arrange their figures to cover a surface completely. Ask them
to share arrangements and discuss the pattens they see. (5.7B, 5.8B,
5.14D, 5.15A, 5.16A))
- Ask students to try to find shapes that
cannot be used to cover the plane without gaps or overlapping. Have
them share ideas about why these shapes and arrangements do not work.
(For example, the angles that meet don't complete a circle so they
leave a gap, or they make more than a circle and overlap.) (5.7A,
B; 5.15A, B; 5.16A)
- Give each student just one pattern block.
Have each student place this polygon in the middle of a blank piece
of paper and trace around it. Have students continue to trace their
polygons again, lining them up with any side of a previously traced
image. Students should continue until they have covered the entire
page. Teachers can also demonstrate their arrangements using pattern
block pieces on the overhead projector. (5.8A, 5.14D)
- After practicing
making tessellations with the pattern blocks, have students create
their own geometric shapes and cut out 15 of them (a possible homework
assignment). Students should test their shapes to see if they will
tessellate. Make and post a "will work/won't work" wall chart on which
students can paste up examples of shapes that will tessellate and
shapes that will not tessellate. (5.8A, 5.14D, 5.16A)
- See "The 'Nibble' Technique" on
p. 9 of the referenced article in Arithmetic Teacher to explain how
to alter polygons and create irregularly shaped figures that also
tessellate. Give students many opportunities to try all the techniques
of making a shape that tessellates. (5.8A, B; 5.14D)
- Students
should create poster-sized tessellations using shapes they like.
See "The Art in Tessellations" on pp. 11-12 of the article for lesson
suggestions. (5.8A, B; 5.14D)
Teacher Notes (to personalize the lesson for your classroom)
Guiding Questions (to engage students in mathematical thinking during the lesson)
- What is a tessellation? (5.15B)
- What is a polygon? (5.15B)
- What are some polygons that will tessellate? How do you know? (5.7A,
B; 5.14D)
- What are some polygons that will not tessellate? How do you know?
(5.7A, B; 5.14D; 5.16A)
- What do you notice about the polygons that
do tessellate? (5.7A, B; 5.8B; 5.15A; 5.16A)
- What do you notice about the
polygons that don't tessellate? (5.7A, B; 5.15A)
- What is a rotation? A translation? A reflection? (5.8B, 5.15B)
- How are you using rotations, translations, and reflections
to create tessellations? (5.8A, B; 5.14D)
- How did you use rotations, translations,
or reflections to make your own shape to tessellate? (5.8A,
B; 5.14D)
Teacher Notes (to personalize the lesson for your classroom)
Summary Questions (to direct students' attention to the key mathematics in the lesson)
To encourage students to make generalizations about tessellations from the examples and nonexamples they have observed, ask questions such as:
- Which shapes tessellated? How did you know? (5.7B, 5.14D, 5.15A)
- What did the shapes that tessellated have in common? (5.7A, 5.15A, 5.16A)
- Which shapes did not tessellate? How did you know? (5.7B, 5.14D, 5.15A)
- What did the shapes that did not tessellate have in common? (5.7A,
5.15A, 5.16A)
- How did you make shapes that would tessellate? (5.8A,
B; 5.14D)
- What attributes of a shape can tell you whether it will tessellate
or not? (5.7A, 5.16A)
To highlight the role played by transformations in creating tessellations, ask questions such as:
- How is the position of this shape in the tessellation related to the position
of this other shape? (It is a translation, rotation, or reflection.) (5.8B,
5.15B)
- Which of the tessellations on display used translations? reflections?
rotations? How can you tell? (5.8B, 5.16B)
- Which transformations did
you use to make your tessellation? (5.8A, B)
- Which transformations
did you use to make your original shape to tessellate? (5.8A, B)
- How
would you describe to someone a translation? a rotation? a reflection?
(5.15A, B)
Teacher Notes (to personalize the lesson for your classroom)
Assessment Task(s) (to identify the mathematics students have learned in the lesson)
- Have each student create a poster-sized tessellation and write a short
description of their process, using appropriate geometric vocabulary.
- Have
students record in their journals, using appropriate geometric vocabulary,
what they have discovered about tessellations, e.g. how they can tell whether
a shape will tessellate or not.
Teacher Notes (to personalize the lesson for your classroom)
Extension(s) (to lead students to connect the mathematics learned to other situations, both within and outside the classroom)
- Students can make a scrapbook of tessellations found in the world around
them (e.g. using pictures in magazines and snapshots of examples).
- Students
can make a shape resembling one of the states in the U.S. that will tessellate.
Teacher Notes (to personalize the lesson for your classroom)