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.
Measurement Topic
This standard is reported on the report card in these quarters as follows:
4th Grade Students Learning 4th Grade Standards
Quarter 1
Quarter 2
Quarter 3
Quarter 4
Report Card Measurement Topic:Demonstrates understanding of measurement and geometry.
3rd Grade Students Learning 4th Grade Standards
Quarter 1
Quarter 2
Quarter 3
Quarter 4
Report Card Measurement Topic:Demonstrates understanding of measurement, data and geometry.
Learning Targets
Explain what symmetry is.
Identify and draw lines of symmetry.
About the Math
A line of symmetry divides a figure into two congruent mirrored parts. A figure may have multiple lines of symmetry. The folded line is called a line of symmetry. A figure is symmetrical if it has a line of symmetry. Essential vocabulary for this standard includes symmetry and line of symmetry. Visit the online dictionaryLinks to an external site. for vocabulary support.
Progression of Standard within Grade 4
This progression informs how to develop the standard within the grade level. This progression is provided by HCPSS Elementary Mathematics.
These tasks can be used with small group or whole group instruction.
Students will use pattern blocks to create a design and draw a line of symmetry that connects to their design. They will switch designs with a partner, and the partner will need to create the mirror image of the design using the line or symmetry. Cut out images from clipart or a magazine.
Cut each image in half and glue each half to a black piece of paper. Students can work to identify the line of symmetry and draw the missing part of the image on the paper. Optional imagesLinks to an external site. are provided and can be printed, if needed.
How do you know that a figure is symmetrical?
What figure can you create that has exactly 2 lines of symmetry? 3 lines of symmetry?
How many lines of symmetry are in a regular hexagon? In a circle? (This should lead to a discussion of when there are an exact number of lines of symmetry and when there could be infinite solutions.)
Think about nature, what are three examples of objects with symmetry?
In what situation is it important for things to be perfectly symmetrical?
Are all polygons symmetrical? All quadrilaterals? All triangles? Sketch examples to show symmetrical as well as non symmetrical figures.
Can you create a design that is made up of three shapes and is still symmetrical? What about with four shapes? Five shapes? (Pattern blocks and tangrams can be used.)
Use 8 or more Pattern Blocks to create a design. What design can you make that has 4 or more lines of symmetry? Record your design and its line of symmetry, and explain how you know it has at least 4 lines of symmetry. (from 20 Thinking Questions for Pattern Blocks)
SLIDE-BASED TASKS
These links are HCPSS created instructional tasks. These tasks are provided in Google slides.These tasks should be used for inspiration and resources, but instruction should start with students having the opportunity to engage with the math first(often involving physical and/or visual models) followed by discussion and explicit instruction to ensure student understanding.
These publications have been provided for each school. They are typically stored in team closets or the media center. Check with your team leader if you cannot find them.
These resource sheets can be used for independent practice, homework, or assessment. They are intended to reinforce procedures and concepts. They should not be used as a source of direct instruction or whole-group practice.
Learning targets identify what students should be able to do. The resources below can be used to measure student understanding of the standard. This rubric can be applied to tasks and observations for assessment and/or grading.
