Grade 7
Math Unit 4
Title
Suggested Time Frame
Geometry and Measurement
Time Frame 4th 6 Weeks
Suggested Duration 30 Days
Guiding Questions
Big Ideas/Enduring Understandings
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Proportional relationship are used in geometry
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How can you show that two objects are proportional?
How do measurements help you describe real-world objects?
Vertical Alignment Expectations
*TEKS one level below*
*TEKS one level above*
TEA Vertical Alignment 5th Grade – Algebra I
Sample Assessment Question
Coming Soon
The resources included here provide teaching examples and/or meaningful learning experiences to address the District Curriculum. In order to address the TEKS to the proper
depth and complexity, teachers are encouraged to use resources to the degree that they are congruent with the TEKS and research-based best practices. Teaching using only the
suggested resources does not guarantee student mastery of all standards. Teachers must use professional judgment to select among these and/or other resources to teach the
district curriculum. Some resources are protected by copyright. A username and password is required to view the copyrighted material. A portion of the District Specificity and
Examples are a product of the Austin Area Math Supervisors TEKS Clarifying Documents available on the Region XI Math website.
7th Math Unit 4
Updated November 19, 2015
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Grade 7
Math Unit 4
Ongoing TEKS
Math Processing Skills
7.01 Mathematical process standards. The student uses mathematical processes to acquire and demonstrate mathematical understanding.
The student is expected to:
(A) apply mathematics to problems arising in everyday life, society, and the workplace;
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Focus is on application
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Students should assess which tool to apply rather than trying only one
or all
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Students should evaluate the effectiveness of representations to ensure
they are communicating mathematical ideas clearly
Students are expected to use appropriate mathematical vocabulary and
phrasing when communicating ideas
Students are expected to form conjectures based on patterns or sets of
examples and non-examples
(B) use a problem-solving model that incorporates analyzing given information, formulating a
plan or strategy, determining a solution, justifying the solution, and evaluating the problemsolving process and the reasonableness of the solution;
(C) select tools, including real objects, manipulatives, paper and pencil, and technology as
appropriate, and techniques, including mental math, estimation, and number sense as
appropriate, to solve problems;
(D) communicate mathematical ideas, reasoning, and their implications using multiple
representations, including symbols, diagrams, graphs, and language as appropriate;
(E) create and use representations to organize, record, and communicate mathematical ideas;
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(F) analyze mathematical relationships to connect and communicate mathematical ideas; and
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(G) display, explain, and justify mathematical ideas and arguments using precise mathematical
language in written or oral communication
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7th Math Unit 4
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Precise mathematical language is expected.
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Grade 7
Math Unit 4
Knowledge and Skills
with Student
Expectations
District Specificity/ Examples
Supplemental Vocabulary: acute angle, lateral surface area, Scalene
triangle, acute triangle, net, semicircle, adjacent angle, obtuse angle,
slant height, complementary angles, obtuse triangle, straight angle,
composite figure, prism, supplementary angle, congruent, pyramid,
surface area, congruent, quarter circle, triangle, congruent segments,
regular pyramid, vertex, equilateral triangle, right triangle,
vertical angle, isosceles triangle, right angle, volume, lateral face, right
triangle, scale model, circle, radius, similar figures,
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7th Math Unit 4
Updated November 19, 2015
Use common benchmarks to compare and order fractions; use place
value when comparing and ordering decimals.
Use vocabulary such as integers, rational numbers, numerator,
denominator, common denominator, place value, greater than, less
than, and equal or equivalent.
Express quantities as percents, fractions, decimals, and whole
numbers.
Order percents, fractions, decimals and whole numbers.
Use operations and definitions to convert between fractions,
decimals, whole numbers, and percents.
Use ratios of corresponding sides and angles to find missing
measurements of sides and angles of similar figures
Describe π as the ratio of circumference over diameter (C/d = π)
Use similar shapes to solve mathematical and real-world problems
Vocabulary
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Attributes
between ratio
proportional
relationships
ratio
similarity
within ratio
circumference
diameter
pi
radius
proportional
relationship
scale drawing
scale factor
similar shape
Suggested Resources
Resources listed and
categorized to indicate
suggested uses. Any
additional resources must
be aligned with the TEKS.
Textbook Resources:
McGraw Hill Ch 4
Web Resources:
Measuring with a
Protractor
Complementary and
Supplementary
angles (Review)
Types of Angles and
Angle Relationships
Vertical Angles
Introduction to
Proportional
Relationships
Circumference Video
Area of Circle Activity
Ratio of
Circumference to
Diameter
Discovering Area
Formula for Circles
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Grade 7
Math Unit 4
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7th Math Unit 4
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Model the relationship of the volume of a rectangular pyramid as
being 1/3 of the volume of a rectangular prism (prism and pyramid
having same size base and same height).
Connect the relationship to the formulas having both congruent
bases and heights.
Use a verbal description to explain the relationship between the
volume of a triangular prism and triangular pyramid. (Prism and
pyramid having same size base and same height).
Use mathematical symbols to represent the relationship between the
volume of a triangular prism and triangular pyramid. (Prism and
pyramid having same size base and same height).
Use models to determine the formulas for the circumference and
area of a circle and to connect models to actual formulas.
Solve for volume of rectangular and triangular prisms.
Solve for volume of rectangular and triangular pyramids.
Determine the circumference and area of circles.
Solve for area of rectangles, triangles, trapezoid, squares,
parallelograms, semi-circles, and quarter circles.
Solve for area of shaded and unshaded parts of given compound
shapes.
Use nets to solve for lateral and total surface area of triangular
prisms, rectangular prisms, triangular pyramids, and rectangular
pyramids.
Find the missing angle measure when given the two angle measures
of a triangle.
Review acute, obtuse, right, and straight angles. (6.8A)
Review complementary and supplementary angles. (4.7E)
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Grade 7
Math Unit 4
7.05 Proportionality –
The student applies
mathematical process
standards to use
geometry to describe
or solve problems
involving proportional
relationships. The
student is expected to:
7.05A
Student’s understanding includes attention to the identification of
common features (attributes), use of examples and non-examples,
classifying or grouping items, naming or labeling the group, and using the
concept in ongoing activities.
Students will identify corresponding sides and corresponding congruent
angles of similar figures using the traditional notation of curved lines for
the angles. Students will write proportions to express the relationships
between the lengths of corresponding sides of similar figures
(relationships between sides of similar figures and within sides of similar
figures).
•7.05A generalize the
critical attributes of
Including, but not limited to:
similarity, including
ratios within and
between similar shapes
o Notation for similar figures aligning corresponding angles
Supporting Standard
and sides: ΔABC ~ ΔLMN
o Corresponding parts of similar figures (alignment as
indicated in similarity statement)
o Corresponding angles are congruent: ∠A≅∠L,∠B≅∠M
o Corresponding sides are related proportionally:
AB/LM=BC/MN=AC/LN
o Likewise, AB/BC=LM/MN
Misconceptions:
• Students may believe that corresponding angles are also
proportional in similar figures
• Over generalizing the phrase “same shape, different size”
• Students believe the scale factor has to be a whole
number
7th Math Unit 4
Updated November 19, 2015
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Grade 7
Math Unit 4
•7.05B describe π as
the ratio of the
circumference of a
circle to its diameter
Readiness Standard
7.05B
The student will derive an approximation for pi by gathering data and
comparing the circumference to the diameter of various circles, using
concrete materials or computer models. Students may have to
determine how to find the radius or diameter when given the
circumference, based on the understanding of pi=circle/diam. Students
will also be able to leave answers as exact (with pi on the answer) rather
than getting an approximation.
Example:
Given several circular items (jars, lids, coffee cans, plates, etc.) and tape
measures, students will measure and record the diameter and
circumference of each item. Then they will divide the circumference by
the diameter to the nearest tenth to discover the relationship (pi).
Misconceptions:
• Pi changes based on the size of the circle
• Students believe pi = 3.14 (this is an approximation, not
the true value)
•7.05C solve
mathematical and realworld problems
involving similar shape
and scale drawings
Supporting Standard
7.05C
Students determine the dimensions of figures when given a scale.
Students identify the scale factor given two figures. Using a given scale
drawing, students reproduce the drawing at a different scale. Students
understand that the lengths will change by a factor equal to the product
of the magnitude of the two size transformations.
Misconceptions:
• Students believe the scale factor has to be a whole
number
7th Math Unit 4
Updated November 19, 2015
Page 6 of 16
Grade 7
Math Unit 4
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Students look for the difference in lengths of
corresponding sides, instead of the ratio. They think it is
an additive relationship instead of a multiplicative.
When solving for the missing length students use 3 and 8 rather than 3
and 11. See picture below.
Eventually, understand that pi is the ratio of circumference of a circle to
its diameter (7.5B)
Example Circumference Tasks:
Ex.1 - Students measure the diameter of a circular figure with string or
pipe cleaner. They then determine how many of those lengths would be
needed to go around the entire circle. Students should determine it is
close to three. They then create an equation/formula to represent this
finding C=3d
Ex. 2 - see Example in 7.5B
Ex. 3 - AIMS “Around and Across”
7th Math Unit 4
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Grade 7
Math Unit 4
Generate a graph by using the diameters and circumferences of round
objects. Once the data has been collected and a relationship has been
established by analyzing that data, determine a formula for the
circumference of a circle.
Example Area Task 2: (From GATAR):
Area of a Circle Activity:
Students will use grid paper to derive a general rule for estimating the
area of a circle. Students will also participate in a hands-on investigation
of the relationship between the formula for computing the area of a
7th Math Unit 4
Updated November 19, 2015
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Grade 7
Math Unit 4
circle and the formula for the area of a rectangle. Using this relationship,
students will derive the formula for computing the area of a circle.
7.08 Expressions,
Equations, and
Relationships – The
student applies
mathematical process
standards to develop
geometric relationships
with volume. The
student is expected to:
•7.08C use models to
determine the
approximate formulas
for the circumference
and area of a circle and
connect the models to
7th Math Unit 4
Updated November 19, 2015
Misconceptions:
• Students may confuse the terms circumference and area with
what they represent in a circle.
• Students may assume that there are 4 sections in the area of
circle and use a 4 in the formula instead of 3 (pi) if the model is
not explicitly connected to the formula.
7.08C
• Understand that circumference is the perimeter of a circle and
measures the distance around vs. area representing the space
covered.
• Use various tools to measure dimensions of circular figures
• Write algebraic equations/formulas to represent the relationships
discovered in an exploration
Page 9 of 16
Grade 7
Math Unit 4
the actual formulas
Supporting Standard
7.09 Expressions,
equations, and
relationships – The
7.09B
student applies
• Find the circumference of a circle by substituting a value for the
mathematical process
diameter or the radius into the formula C=πd or C=2πr
standards to solve
• Understand the relationship between circumference, diameter,
geometric problems.
and radius.
The student is expected
• Understand that pi is a ratio of circumference to diameter.
to:
• Student should be able to solve for any of these when given
another.
• Students may be asked to determine the radius or diameter when
•7.09B determine the
given the circumference or area. Therefore they will need to be
circumference and
able to solve equations for which the variable is not already
area of circles
isolated.
Readiness Standard
• 113.04 = π(d) vs π(6) = C
Example 1:
The seventh grade class is building a mini-golf game for the school
carnival. The end of the putting green will be a circle. If the circle is 10 ft
in diameter, how many square feet of grass carpet will they need to buy
to cover the circle? How might someone communicate this information
to the salesperson to make sure he receives a piece of carpet that is the
correct size? Use 3.14 for pi.
Solution: Area = πr2
Area = (3.14)(52)
Area = 78.5
To communicate this information, ask for a 9ft by 9ft square of carpet.
7th Math Unit 4
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Grade 7
Math Unit 4
Example 2:
The center of the circle is at (5,-5). The radius of the circle is 4. What is
the area of the circle?
Solution:
Using the formula, Area =πr2 the area of the circle is approximately
50.24
Students build on their understanding of area from 6th grade to find the
area of left-over materials when circles are cut from squares and
triangles or when squares and triangles are cut from circles.
Misconceptions:
• Students may confuse the terms circumference and area with
what they represent in a circle.
• Common computation errors include: multiplying by 2 instead of
squaring the radius, using radius in place of diameter (and vice
versa), not following the order of operations when solving.
7.08 Expressions,
Equations, and
Relationships – The
student applies
mathematical process
standards to develop
geometric relationships
with volume. The
7.08A
student is expected to: The volume of a pyramid is ⅓ the volume of prism with congruent bases
and height. Therefore, it takes the volume of 3 pyramids to fill the prism
•7.08A model the
relationship between
Exploration 1:
the volume of a
7th Math Unit 4
Updated November 19, 2015
Textbook Resources
McGraw Hill Ch 8
Web Resources:
Perimeter
Area
Composite Figures
Perimeter Video
Area Video
Area & Perimeter of
Composite Figures
Discovering Area
Types of Triangles
Page 11 of 16
Grade 7
Math Unit 4
rectangular prism and
a rectangular pyramid
having both congruent
bases and heights and
connect that
relationship to the
formulas Supporting
Standard
Using hollow geometric solids, have students estimate the relationship
between the volume of the pyramid and prism with congruent bases and
height. How many pyramids would fit in the prism?
Fill the pyramid with rice, water, etc. and pour into the prism. Ask the
students to refine their estimate. How full is the prism? How many
pyramids full would fit in the prism?
Continue to fill the pyramid and pour into the prism to demonstrate that
it takes 3 pyramid-fulls to fill the prism. Therefore, the volume of the
pyramid is ⅓ the volume of the prism, hence the formula.
Exploration 2:
From GATAR and Mathematics TEKS Connections: Geometry
Students use nets/templates to create three congruent square pyramids
and manipulate them to form a prism of the same base area and height.
•7.08B explain verbally
and symbolically the
relationship between
the volume of a
rectangular prism and
a rectangular pyramid
having both congruent
bases and heights and
connect that
relationship to the
formulas Supporting
Standard
7th Math Unit 4
Updated November 19, 2015
Formula for Triangles
Finding the Area of
Trapezoids
Finding the Area of
Irregular Shapes
Parallel Pinwheel
Finding Triangle
Angles
Triangle Sides
Volume of Prisms
Volume of Pyramids
Misconceptions:
• Students often confuse the vocabulary base, length, height, “B”
(base area), when moving between 2- and 3- dimensional figures
7.08B
Students should connect prior learning related to the volume of
rectangular prisms and pyramids to triangular prisms and pyramids.
For example: The volume of a pyramid is ⅓ the volume of prism with
congruent bases and height. Therefore, it takes the volume of 3 pyramids
to fill the prism.
Students should understand that
V= ⅓Bh, where B= ½bh (area of base triangle)
Misconceptions:
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Grade 7
Math Unit 4
7.09 Expressions,
equations, and
relationships – The
student applies
mathematical process
standards to solve
geometric problems.
The student is expected
to:
•7.09A solve problems
involving the volume of
rectangular prisms,
triangular prisms,
rectangular pyramids,
and triangular pyramid
Supporting Standard
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Students often confuse the vocabulary base, length, height, “B”
(base area), when moving between 2- and 3- dimensional figures.
Students believe that whatever face the prism is sitting on is the
base of the figure.
7.09A
“Know the formula” does not mean memorization of the formula. To
“know” means to have an understanding of why the formula works and
how the formula relates to the measure (area and volume) and the
figure. This understanding should be for all students.
Example:
Jennie purchased a box of crackers from the deli. The box is in the shape
of a triangular prism (see diagram below). If the volume of the box is
3,240 cubic centimeters, what is the height of the triangular face of the
box? How much packaging material was used to construct the cracker
box? Explain how you got your answer.
Solution:
Volume can be calculated by multiplying the area of the base (triangle)
by the height of the prism. Substitute given values and solve for the area
of the triangle
V = Bh
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Grade 7
Math Unit 4
3,240 cm3 = B (30cm)
3,240 cm3 = B(30cm)
30 cm 30 cm
108 cm2 = B (area of the triangle)
To find the height of the triangle, use the area formula for the triangle,
substituting the known values in the formula and solving for height. The
height of the triangle is 12 cm. The problem also asks for the surface area
of the package. Find the area of each face and add:
2 triangular bases: ½ (18 cm)(12 cm ) = 108 cm2 x 2 = 216 cm2
2 rectangular faces: 15 cm x 30 cm = 450 cm2 x 2 = 900 cm2
1 rectangular face: 18 cm x 30 cm = 540 cm2
Adding 216 cm2 + 900 cm2 + 540 cm2 gives a total surface area of 1656
cm2.
Misconceptions:
• Students often assume that the face a solid figure is sitting on is
its base, this causes particular difficulty in triangular prisms.
• Students often confuse the vocabulary base, length, height, “B”
(base area), when moving between 2- and 3-dimensional figures.
•7.09C determine the
area of composite
figures containing
combinations of
rectangles, squares,
parallelograms,
trapezoids, triangles,
semicircles, and
7th Math Unit 4
Updated November 19, 2015
7.09C
Students need to be able to substitute values into a formula and
evaluate. Students need to be able to break a composite figure into
shapes for which there is a known area formula. Students will use
individual formulas learned previously in conjunction to find the area of
composite figures. Students should understand that there is often more
than one way that a composite figure can be broken up.
Page 14 of 16
Grade 7
Math Unit 4
quarter circles
Readiness Standard
•7.09D solve problems
involving the lateral
and total surface are of
a rectangular prism,
rectangular pyramid,
triangular prism and
triangular pyramid by
determining the area
of the shape’s net
Supporting Standard
Example Problems/ Tasks:
Example 1: If a circle is cut from a square piece of plywood, how much
plywood would be left over?
Misconceptions:
• Students think that there are formulas that work for all shapes
and not understand that they may need to use multiple formulas
together for composite shapes.
• Students may have trouble using the given measurements to find
missing dimensions that are needed to solve for the composite
area.
7.09D
Students should understand that surface area is the sum of the area of
faces. Total surface area is the sum of all faces including the bases.
Lateral surface area is the sum of the faces excluding the bases.
“Knowing the formula” does not mean memorization of the formula. To
‘know” means to have an understanding of why the formula works and
how the formula relates to the measure (area and volume) and the
figure. This understanding should be for all students.
Surface area formulas are not the expectation with this standard.
Building on work with nets in the 6th grade, students should recognize
that finding the area of each face of a three-dimensional figure and
adding the areas will give the surface area. No nets will be given at this
level; however, students could create nets to aid in surface area
calculations.
Misconceptions:
• Students often have trouble determining whether they are
looking for total or lateral surface area.
7th Math Unit 4
Updated November 19, 2015
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Grade 7
Math Unit 4
7.11 Expressions,
equations, and
relationships – The
student applies
mathematical process
standards to use
statistical
representations to
analyze data. The
student is expected to:
•7.11C write and
solve equations using
geometry concept,
including the sum of
the angles in a triangle,
and angle relationships
Supporting Standard
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Students may be confused about which faces are the bases and
which are the lateral faces.
Students often confuse the vocabulary base, length, height, “B”
(base area), and “P” (base perimeter) when moving between 2and 3- dimensional figures.
7.11C
Students need to be able to recall previous geometry learning including
angles and angle sums (could also include sum of angles in other
polygons, angle pairs, perimeter, area, volume).
Students identify given information in a geometric figure and relate to a
formula. Substitute information from a geometric figure into a formula
and create an equation to represent a geometric situation/relationship.
Misconceptions:
• Students may not understand that equations can be used to
represent geometric situations.
• Students may not understand that formulas are just a kind of
equation.
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Updated November 19, 2015
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