Lesson Plan: Building a Tetrahedron
PLANNING
Grade Level:
Subject:
Content Standard(s):
Purpose of the Lesson:
Links to Prior Knowledge or
Experience:
(i.e., academic background/ prior
learning; knowledge/skills gained in or
out of school; interests)
Performance Objective(s):
Assessment/
Evaluation:
Scaffolds for English learners
& Children with Special
Needs:
Academic Language:
Materials:
(e.g., books, charts, models,
manipulatives, realia, technology—for
both teacher and students)
1
Math
Common Core, Grade 1
Geometry
1.G.A. Reason with shapes and their attributes
1. Distinguish between defining attributes (e.g., triangles are closed and threesided) versus non-defining attributes (e.g., color, orientation, overall size);
build and draw shapes to possess defining attributes.
2. Compose two-dimensional shapes (rectangles, squares, trapezoids,
triangles, half-circles, and quarter-circles) or three-dimensional shapes (cubes,
right rectangular prisms, right circular cones, and right circular cylinders to
create a composite shape, and compose new shapes from the composite
shape.
Students will build 2D and 3D shapes in order to better visualize shapes and
understand dimensionality. Additionally, students will practice using
appropriate academic language related to shapes.
Students have drawn 2D shapes according to attributes on whiteboards and
paper. (E.g., students have been directed to “Draw a shape that has 3 corners”
or “Draw a shape that has 4 sides of equal length.”) Students have done 2D
and 3D shape identification. Students have been introduced to, but not deeply
dealt with, the faces of 3D shapes. Students have done shape exploration
through art, a short walk around campus, and through poetry.
Students will compose 2D shapes (triangles, rhombus, trapezoid), then build
in another dimension to create a 3D tetrahedron by using toothpicks and
gumdrops (combination of direct and investigative).
Toothpick and gumdrop tetrahedron and informal observation/monitoring.
(Could the student construct it? Was the student using the academic
language?)
 Document camera to show step-by-step process
 Model of completed tetrahedron
Vocabulary: corners, sides, faces, edges, vertices, triangle, rhombus,
trapezoid, pyramid, tetrahedron, 2D, 3D
Language Demands: understand and follow verbal instructions, ask questions,
verbally communicate with peers.
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toothpicks
gumdrops
napkin “placemat” (optional)
document camera as an instructional tool
INSTRUCTION
What the Teacher Does
What Students Do
Motivate/Engage (5 min)
1. shows completed model of
tetrahedron
2. Explains that students will get
to make a tetrahedron by
following instructions stepby-step on the document
camera. Explains
management of manipulatives
as needed (e.g., students are
using only the prepared
materials in a plastic bag,
students can only eat X
number of gumdrops, students
are not to misuse toothpicks,
etc.).
Procedures &
Activity/Activities:
Motivate: set purpose, activate prior
knowledge, connect to prior learning,
build background, state objectives, grab
attention and relate students’
experiences to objectives.
Model: Guide, demonstrate, check for
understanding.
Practice: apply the skill or to gain deeper
understanding of a concept.
(Time: 25 min total)
1. Students observe completed
model of tetrahedron, ask
questions, and make
observations about the
attributes of the tetrahedron.
Model/Practice (20 min)
1. Teacher begins by asking
each student to compose a
shape that has 3 sides.
2. Teacher asks students to add
onto the triangle to form a
rhombus.
3. Teacher has students add onto
the rhombus to make a
trapezoid.
4. Teacher prompts students to
add more toothpicks and
gumdrops to make a larger
triangle.
5. Teacher demonstrates how to
build upward (adding a
dimension—now the shape
becomes 3D) to make a
pyramid in one corner of the
triangle.
6. Teacher demonstrates how to
add a pyramid to each of the
other corners of the large
triangle
7. Teacher demonstrates how to
connect the top vertexes of
1. Students build a shape with
three sides.
2. Students build a rhombus.
3. Students build a trapezoid.
4. Students turn their trapezoid
into a large triangle.
5. Students build 1 pyramid.
6. Students build pyramids at the
remaining 2 corners of the
large triangle.
7. Students connect the top
vertexes of the 3 pyramids
the 3 pyramids.
8. Teacher prompts students to
build another pyramid to
complete the tetrahedron.
Closure:
Summarize learning/objective, eliciting
responses from students.

Regroup. Teacher reviews academic vocabulary with students, having
students point to the faces, vertices, edges, etc. of their completed
tetrahedrons.

A few students discuss share what they liked (or did not like about the
project), what was easy, and what was difficult/challenging.
(Time: 3 min)
Reflections/Students:
(Time: 3 min)
Reflections/Teacher:
8. Students build another
pyramid to complete the
tetrahedron.
How successful were students in completing the assignment? What was the
frustration level or level of ease for each student? Did the assignment help
students to really visualize and understand dimensionality and attributes of
shapes?