#3238. Symmetry

Mathematics, level: all
Posted Mon Oct 11 05:36:44 PDT 2004 by Sara Ash (saraash722@yahoo.com).
University of Pittsburgh at Johnstown, Johnstown, USA
Materials Required: pattern blocks, plain white paper, markers
Activity Time: 30-45 minutes
Concepts Taught: symmetry

New Vocabulary: symmetry, symmetrical shapes, line of symmetry

Instructional Procedures:

Anticipatory Set
o Draw some symmetrical shapes on the board, including some of the geometric shapes the students have been learning, and ask the students what those shapes have in common. Take some guesses from the students.
o Tell the students that these shapes are all symmetrical.
o Have some of the students tell you what they think symmetry means.
o Explain that symmetry is when a figure has two sides that are mirror images of one another. Tell them that you can draw a line through a picture of the object and along either side the image would look exactly the same. Explain that this line would be called a line of symmetry.
o Have the class give other examples of things that look symmetrical that they find it nature, at school, at home, and outside.

Developmental Activities
o Tell the students that they will be doing an activity that involves making symmetrical designs. Explain to the class that you will be giving everyone a sheet of white paper and that each table will get a container of pattern blocks. Tell them that once they receive their paper they will fold it in half, open it back up, and set it in front of them so the fold goes up and down. Tell them they will use the pattern blocks to make a design on the left side of their paper. Tell them they will have 5 minutes to make the design with the pattern blocks.
o Pass the paper out to the students and have them fold in half. Once everyone's paper is folded, tell the class they can begin making the design on the left side of the fold.
o After five minutes have passed, tell the students to stop making their design and explain that for next part of the activity they will be completing the designs to make them symmetrical. Tell the students that they will be moving around the table to the seat to their left and that once they get to the seat they will have to complete the design by adding pattern blocks to the right half of the paper, making a mirror image of the left side. Remind them that the fold line on the paper will act as the line of symmetry and that they must think carefully about what is on the left side so they can add pattern blocks to the right side.
o Tell the students that they will have 10 minutes and have them start completing the design. Walk around to check if everyone understands by observing whether or not they are making symmetrical designs.
o After everyone has completed the designs, tell the students to go back to their original seats. Once there, have the students check the design in front of them to make sure that it is symmetrical. If they see something that needs fixed or added they should tell the student that did it and help them to fix it.
o After all of the designs are checked for symmetry, have the students put the pattern blocks back in the container and place the container and piece of paper in the middle of the table.

Closure
o Review the meanings of symmetry and line of symmetry.
o Tell the students that next, they will be doing a fun activity called "Name Creatures." Show a demonstration of the activity using a pre-made example. Explain that you will be giving each student another piece of white paper. Tell them that they will need to fold the paper in half length-wise. Then they should write their name with a dark marker in large cursive letters on the fold. Then they should turn the paper over so that they can trace their name on the other side of the paper. When they unfold the paper, their names should make a symmetrical design, with the fold line being the line of symmetry. Tell the students that after they have their names drawn they should look at the design and try to make some kind of creature out of it by coloring it and adding other lines. Emphasize that everything they add to it should be added on both sides so that it stays a symmetrical design. Tell them they will have about 15 minutes to complete their creatures.
o Pass the paper out and have the students do the activity while you walk around observing their work. Encourage the students to be creative when making their creature!
o Once the students are finished, have them share their creatures with their classmates.
o Collect the creatures for assessment.
Assessment:
• Observe students' participation in the discussions.
• Observe the students' ability to find lines of symmetry in the shapes.
• Observe the students' ability to make symmetrical shapes with pattern blocks.
• Collect the students' Name Creatures to check for symmetry.

Enrichment/Extension: Have the students create butterflies by folding a sheet of construction paper in half and cutting out half of a butterfly shape so that when it opens it will be a whole butterfly. Then have the student thickly spread or squirt paint on one of the inside sides and folding the paper back together so the image transfers to the other half, making a symmetrical design.

Technology Integration:
• One Computer in the Classroom
o Using a drawing program like Paint, demonstrate symmetry by drawing a symmetrical pattern and show it on the projector. Then whenever students have free time in the next couple of days they can make their own symmetrical design to print out and turn in for evaluation.
• Six Computers in the Classroom
o Divide the students into six groups. Randomly assign each student in each group a number. Number ones will begin making a symmetrical design using a drawing program like Paint. Then number twos will add on to the design, keeping it symmetrical. The other students will follow according to their assigned numbers. Have them print the final design for evaluation.
• Every Child has a Computer in the Classroom
o Have the students make symmetrical designs using a drawing program like Paint. Have them print them out and turn them in for evaluation.