Unit 8 – Geometry
Unit Essential Question(s):
1. What are the properties of two-dimensional geometric figures?
2. How do you list properties, classify, draw and identify geometric figures in two
dimensions?
Vocabulary: point, line, line segment, ray, angle, right angle, acute angle,
obtuse angle, perpendicular line, parallel line, two-dimensional figure, right
triangle, symmetry, mirror, scalene triangle, obtuse triangle, lines of
symmetry
Big Ideas/Understanding:
• Students will understand that geometric figures can be analyzed and classified
based on their properties.
• Students will understand that parallel sides, particular angle measures, and
symmetry can be used to classify geometric figures.
• Students will understand that two lines are parallel if they never intersect and are
always equidistant.
• Students will understand that two lines are perpendicular if they intersect in right
angles (90 degrees).
• Students will understand that lies of symmetry for a two-dimensional figure occur
when a line can be drawn across the figure such that the figure can be folded along
the line into matching parts.
• Students will understand that angle measurement can be though of as a measure
of rotation.
• Students will understand that the measure of an angle does not depend on the
length of its sides.
Lesson #1:
Description: Identify point, lines, line segments, rays, angles ( right, acute, obtuse)
and perpendicular and parallel in two dimensional figures.
Essential Question(s):
1. How do identify point, lines, line segments, rays, angles (right, acute, obtuse) and
perpendicular and parallel in two dimensional figures?
Lesson #2:
Description: Draw points, lines, line segments, rays, angles (right, acute, obtuse)
and perpendicular and parallel lines. Identify these in two-dimensional figures.
Essential Question(s):
1. How do you draw points, lines, line segments, rays, angles, and perpendicular and
parallel lines?
2. How do you identify points, lines, line segments, rays, angles, and perpendicular and
parallel lines in two-dimensional figures?
Lesson #3:
Description: Recognize and identify triangles.
Essential Question(s):
1. How do you recognize right, scalene and obtuse triangles? How do you identify right,
scalene and obtuse triangles?
Lesson #4:
Description: Classify two-dimensional figures based on the presence or absence of
parallel or perpendicular lines, or the presence or absence of angles of a specified
size. Recognize right triangles as a category, and identify right triangles.
Essential Question(s):
1. How do you classify two-dimensional figures based on parallel or perpendicular
lines?
2. How do you classify two-dimensional figures based on angles of a specified size?
Lesson #5:
Description: Measure angles in whole number degrees using a protractor. With
the aid of a protractor, sketch angles of specified measure.
Solve addition and subtraction problems to find unknown angles on a diagram in
real-world and mathematical problems. (Angle must be adjacent and nonoverlapping.)
Essential Question(s):
1. How can you use a protractor to measure angles?
2. How can you find the missing angle measurement?
Lesson #6:
Description: Recognize a line of symmetry for a two-dimensional figure as a line
across the figure such that the figure can be folded along the line into mirroring
parts.
Essential Question(s):
1. How do you know if the figure is symmetrical?
2. How do you recognize a line of symmetry for a figure through mirroring?
Lesson #7:
Description: Identify line symmetric figures and draw lines of symmetry (up to
two lines of symmetry)
Essential Question(s):
1. How do you identify line-symmetrical figures?
2. How do you draw lines of symmetry?
Web-based Resources:
https://www.khanacademy.org/math/geometry/intro_euclid/v/lines--line-segments--and-rays
http://www.brainpopjr.com/math/geometry/pointslinessegmentsrays/preview.weml
http://mrnussbaum.com/lines/
http://learnzillion.com/lessons/1707-count-sides-and-angles-to-identify-polygons
http://learnzillion.com/lessons/1708-identify-quadrilaterals-based-on-attributes
http://learnzillion.com/lessons/1709-compare-quadrilaterals-based-on-attributes
http://learnzillion.com/lessons/1710-classify-quadrilaterals-by-looking-at-multiple-attributes
http://www.virtualnerd.com/common-core/grade-5/5_G-geometry/B/4/quadrilateral-types
http://www.virtualnerd.com/common-core/grade-5/5_G-geometry/B/3/quadrilateral-definition
http://www.virtualnerd.com/common-core/grade-5/5_G-geometry/B/3/rectangle-definition
http://www.virtualnerd.com/common-core/grade-5/5_G-geometry/B/3/definition-square
http://www.virtualnerd.com/common-core/grade-5/5_G-geometry/B/3/rhombus-definition
http://studyjams.scholastic.com/studyjams/jams/math/geometry/classify-triangles.htm
http://www.studyzone.org/mtestprep/math8/f/triangle5l.cfm
https://www.khanacademy.org/math/cc-fourth-grade-math/cc-4th-geometry-topic/cc-4th-classifyingshapes/v/scalene-isosceles-equilateral-acute-right-obtuse
https://www.khanacademy.org/math/cc-fourth-grade-math/cc-4th-geometry-topic/cc-4th-classifyingshapes/e/triangle_types
https://www.khanacademy.org/math/geometry/parallel-and-perpendicular-lines/Angle_basics/v/using-aprotractor
https://www.khanacademy.org/math/geometry/parallel-and-perpendicularlines/Angle_basics/v/measuring-angles