Pattern Matching

In this session we explore shapes and pictures and classify these as having line symmetry and not having line symmetry. Students are encouraged to use their own language to describe objects and pictures that have symmetry.

1. Gather the students in a circle on the mat. Have a collection of objects and pictures in the centre along with mirrors, straws, scissors, magazines and two pieces of chart paper.
   

   We are going to look through these pictures and objects and find out if any have two sides that match.

2. Use a basic shape, e.g. a triangle or square cut out from a piece of paper, and show how, if it is folded in half, the two sides match.
3. Use a mirror to show how two sides of one of the pictures on the mat match each other.
4. Draw a line of symmetry to show where to fold the shape or place the mirror to demonstrate the match.
   I am going to draw a line on this shape and this picture to show that the sides match if they are folded down this line.
5. Get the students to explore the objects and pictures on the mat and to choose one that has a line of symmetry and one that doesn’t. The language of symmetry could be introduced to describe the matching shapes.
   Why have you chosen that object?
   Try using the mirror to see if the sides will be the same.
   Can you put a straw down the line of symmetry? (folding line)
6. Get the students to sort their shapes (those that have symmetry and those that don’t) onto the two pieces of chart paper and to state why they have placed them where they have. Get the students to check that each shape, object or picture is being placed on the appropriate piece of paper. Encourage students to identify the line of symmetry and for some pictures to indicate if there is more than one line.
7. The students contribute to captions to describe the two charts and how the objects have been classified.
8. Let the students independently explore the idea by using magazines to locate a picture of something with a line of symmetry and something with no line of symmetry. Students paste these pictures onto a piece of paper divided in half. They draw a line or paste a straw onto the symmetrical picture to show the line of symmetry and provide a caption for the two pictures.

Exploring

Over the next few days students explore things that have line symmetry (or reflection symmetry) as they complete a variety of activities using shapes, familiar objects, pictures, patterns. The students could be organised into small groups and rotated through the activities or they could work independently choosing from a range of activities or marking off completed activities on a contract. The teacher needs to play an active role in interacting with the students and ensuring that the concepts are being developed and explored appropriately.

1. Pattern Match
   Templates showing a pattern made with mosaic tiles are provided for the students. Each pattern stops at a line.
   Students use mosaic tiles to complete the pattern so that it matches on each side of the line. The line is a line of symmetry.
   
   Teaching Notes:
   Templates could be made by drawing around mosaic tiles or setting up a pattern using the tiles and photocopying it. BSM 2-3-87 has some of these cards.
   
2. Symmetrical Patterns BSM 2-3-9
   Students use the cards showing reflective symmetrical patterns, which they copy using concrete materials.
   Students can locate the line of symmetry using a mirror or placing a straw (string, skewer, pencil, ice-block stick) along the line.
3. Splodge Pictures
   Provide the students with pre-folded A4 paper or with a line down the middle.
   Students paint splodges and patterns on one side of the paper.
   The paper is then folded to create the matching pattern on the other side of the paper.
   Students provide a caption about their picture either to describe how both sides are the same or to say something about the process for making the picture.
4. Place Mats
   Students fold a half A4 piece of paper in half one way and then the other.
   They cut out shapes on the folds.
   Unfold the shapes and mount them on paper with a contrasting colour.
   Students identify the lines of symmetry by drawing them in with a coloured pen.
   Some students may want to use more folds and so create a more complicated pattern.
5. Leaf Lines
   Students stick a leaf onto a piece of paper.
   They draw a line running down the centre of the leaf to show the line of symmetry.
6. Pegboard Patterns (BSM 3-3-8)
   Students use the pattern cards; they copy the patterns onto the pegboards.
   Students locate the line/lines of symmetry.
   Students create their own symmetrical patterns and get a friend to locate the line of symmetry.
7. Pegboard and Pattern "Snap" (BSM 3-3-51)
   Students play as per the instructions in BSM booklet Cycle 3 Module 3 activity 51.
8. Symmetrical Me
   Students look in a mirror to see if both sides of their face look the same.
   Students take an outline drawing of a person and fold it in half to show a line of symmetry.
   They add details to the person to make it a picture of themselves, for example, clothing, facial features, hair.
   Students provide a caption about being the same on both sides.

Reflecting

In this session we review the activities that have been completed over the last few days and revisit the class charts and individual charts made in the initial activity. The students are provided with opportunities to demonstrate their understanding of symmetry, to find examples of line symmetry within the classroom, and to create a symmetrical pattern to contribute to a class book.

1. Gather the students on the mat and get them to describe the sorts of activities they have been involved in over the week. Encourage them to talk about patterns that match and about lines of symmetry.
   What was special about the patterns we made with the pegboards?
   Why did we put a line down the pictures of ourselves?
2. Revisit the charts made in the initial session and talk about the way the objects have been grouped.
   Why was this picture of a house put on this chart?
   Can you find the line of symmetry in this picture?
3. Get students to look at large objects in the classroom and to think about line symmetry, for example, the door, tables, chairs, the board. With a partner, get the students to find three things in the classroom that have line symmetry and to identify the line.
4. Gather the students back on the mat and show them a range of craft materials; coloured ice block sticks, pom poms, stickers, ink stamps, coloured toothpicks, pipe cleaners.
5. Give each student a piece of paper and get them to fold it down the middle.
6. Get the students to create a pattern by sticking on the craft materials on one side of the paper and then to mirror it on the other.
7. Get each student to provide a caption and to draw in the line of symmetry.