Symmetry in Action
10 min
Narrative
This Warm-up prompts students to carefully analyze and compare attributes of two-dimensional figures with attention to the number of sides, symmetry, and presence of parallel and perpendicular lines. In making comparisons, students have a reason to use language precisely (MP6). The activity enables the teacher to observe the attributes that students notice intuitively and hear the terminologies they feel comfortable using.
Launch
- Groups of 2
- Display the image.
- “Pick 3 that go together. Be ready to share why they go together.”
- 1 minute: quiet think time
Teacher Instructions
- “Discuss your thinking with your partner.”
- 2–3 minutes: partner discussion
- Share and record responses.
Student Task
Which 3 go together?
Sample Response
Sample responses:
A, B, and C go together because:
- They show four sides.
A, B, and D go together because:
- At least 2 sides are the same length.
A, C, and D go together because:
- They have a right angle.
- They have one pair of perpendicular sides.
B, C, and D go together because:
- All segments meet other segments.
Activity Synthesis (Teacher Notes)
- “What attributes of the figures did you pay attention to as you tried to find which 3 go together?"
- As students share, highlight the attributes on the images that they are comparing.
- If no students mention parallel sides as an attribute to consider, ask them about it.
Standards
- 4.G.1·Draw points, lines, line segments, rays, angles (right, acute, obtuse), and perpendicular and parallel lines. Identify these in two-dimensional figures.
- 4.G.2·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. (Two-dimensional shapes should include special triangles, e.g., equilateral, isosceles, scalene, and special quadrilaterals, e.g., rhombus, square, rectangle, parallelogram, trapezoid.)
- 4.G.3·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 matching parts. Identify line-symmetric figures and draw lines of symmetry.
- 4.G.A.1·Draw points, lines, line segments, rays, angles (right, acute, obtuse), and perpendicular and parallel lines. Identify these in two-dimensional figures.
- 4.G.A.2·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.
- 4.G.A.3·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 matching parts. Identify line-symmetric figures and draw lines of symmetry.
15 min
20 min
Knowledge Components
All skills for this lesson
No KCs tagged for this lesson
Symmetry in Action
10 min
Narrative
This Warm-up prompts students to carefully analyze and compare attributes of two-dimensional figures with attention to the number of sides, symmetry, and presence of parallel and perpendicular lines. In making comparisons, students have a reason to use language precisely (MP6). The activity enables the teacher to observe the attributes that students notice intuitively and hear the terminologies they feel comfortable using.
Launch
- Groups of 2
- Display the image.
- “Pick 3 that go together. Be ready to share why they go together.”
- 1 minute: quiet think time
Teacher Instructions
- “Discuss your thinking with your partner.”
- 2–3 minutes: partner discussion
- Share and record responses.
Student Task
Which 3 go together?
Sample Response
Sample responses:
A, B, and C go together because:
- They show four sides.
A, B, and D go together because:
- At least 2 sides are the same length.
A, C, and D go together because:
- They have a right angle.
- They have one pair of perpendicular sides.
B, C, and D go together because:
- All segments meet other segments.
Activity Synthesis (Teacher Notes)
- “What attributes of the figures did you pay attention to as you tried to find which 3 go together?"
- As students share, highlight the attributes on the images that they are comparing.
- If no students mention parallel sides as an attribute to consider, ask them about it.
Standards
- 4.G.1·Draw points, lines, line segments, rays, angles (right, acute, obtuse), and perpendicular and parallel lines. Identify these in two-dimensional figures.
- 4.G.2·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. (Two-dimensional shapes should include special triangles, e.g., equilateral, isosceles, scalene, and special quadrilaterals, e.g., rhombus, square, rectangle, parallelogram, trapezoid.)
- 4.G.3·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 matching parts. Identify line-symmetric figures and draw lines of symmetry.
- 4.G.A.1·Draw points, lines, line segments, rays, angles (right, acute, obtuse), and perpendicular and parallel lines. Identify these in two-dimensional figures.
- 4.G.A.2·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.
- 4.G.A.3·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 matching parts. Identify line-symmetric figures and draw lines of symmetry.