Fun with Symmetry Class 4 Maths Chapter 11 CBSE Notes 2025-26

Symmetry is all around us in nature, objects, and patterns we see each day. In this chapter, you explore how certain designs or shapes can be divided into two equal halves so that both sides look the same. This invisible dividing line in such shapes is called the line of symmetry. Folding a paper and using colour is a fun way to see how symmetry works, and you can discover how the two sides of your pattern turn out to be mirror images of each other.

Making Symmetrical Patterns

You can create symmetrical patterns using simple materials. For example, take a sheet of paper, fold it in half, drop some ink or colour near the fold, and gently press the paper. Once you open the sheet, you will notice that both halves of the paper have identical patterns on either side of the fold. The fold marks the line of symmetry, and you’ve just made a symmetrical design without using any tools! This activity helps you understand how symmetry appears in many everyday things like rangolis, masks, and decorative motifs.

Paper Folding and Airplanes

When making a paper airplane, following step-by-step folding instructions allows you to see symmetry in action. Mark the line of symmetry on your paper as you fold—planes with a clear line of symmetry tend to fly straighter and better than those that are uneven. For instance, if you create both a symmetrical and an asymmetrical plane and fly them, you’ll usually notice that the symmetrical one flies farther and straighter. This is because symmetry helps balance and supports equal distribution of forces.

Fold and Cut Designs

Folding and cutting paper is another engaging way to understand symmetry. If you fold a paper once or twice and then make a cut at a corner or along an edge, the hole or design that appears upon opening the paper will always show symmetrical properties, depending on how you folded. For example, cut a square while the paper is folded twice, and you’ll find that the square cutout is formed at the centre or at multiple points, based on your folding and cutting technique. These simple experiments show how symmetrical shapes can be created and repeated using basic folds and cuts.

Symmetry in Numbers and Letters

Did you know that some digits and letters look the same when seen in a mirror? For instance, digits like 0, 1, and 8 have vertical symmetry, which means their mirror images don’t change. You can investigate which other digits from 0 to 9 have this property by drawing them and placing a mirror in the correct position. Similarly, some 4-digit numbers (like 1001, 8888, etc.) will appear exactly the same when reflected. These playful activities help you recognize which numbers and patterns are symmetrical.

Patterns in letters work the same way. Words such as WOW or CAN might look the same or different depending on where you place the mirror. The line you place the mirror on is called the line of reflection or mirror line. Try writing names or words and see which ones retain the same identity under reflection, just like the reversed AMBULANCE sign on emergency vehicles so it appears correctly in a rear-view mirror.

Mirror Games and Challenges

Mirror games can make learning symmetry interactive. Try guessing numbers and shapes whose mirror images look the same, or create puzzles for your friends using mirrors. Place a mirror on different lines of a shape to check where it appears identical on both sides; these lines are the lines of symmetry. Some shapes might have only one line of symmetry (like the number 1), while others like 8 have more than one.

Symmetry in Shapes and Tile Patterns

Symmetry is also central to the world of shapes. For example, many regular shapes like squares, rectangles, and circles have more than one line of symmetry. When you trace shapes or fold them, the lines where the two halves match exactly are lines of symmetry. You might be asked to draw shapes on dot grids and check which ones are symmetrical, then to draw their lines of symmetry. Complex or irregular shapes might have fewer or no lines of symmetry.

Tile patterns demonstrate symmetry beautifully. In floors or wall designs, you may find tiles repeated in such a way that they fit without any gaps or overlaps. These tiles are often symmetrical, and by sliding, flipping, or rotating them, you can create a wide range of new patterns. Some tiles might have more than one line of symmetry, and groups of shapes can form repeating symmetrical units in a pattern.

Creating Tiles and Floor Patterns

Artisans and designers often use symmetry while designing stylish tiles and grand flooring. You can design your own creative tiles using paper cutouts, a rangometry kit, or by drawing. For practice, make new floor patterns, paying attention to whether the shapes fit together perfectly and whether your design repeats with symmetry. When you pick colours or combine shapes, try to notice if the arrangement maintains symmetrical balance.

Making Creative Walls

You can also make patterned walls, such as creating a ‘catty wall’ by tracing, cutting, and sliding paper pieces to form shapes like cats. When the tiles are put together, the cat patterns repeat in a symmetrical way and fit together without gaps or overlaps. This kind of activity connects symmetry to hands-on creativity.

Nature Walk and Symmetrical Designs

Symmetry is everywhere in nature—from butterflies and leaves to flowers and animal bodies. When you go on a nature walk, you can collect leaves and classify them into symmetrical and non-symmetrical groups. Many leaves, especially those with a single main vein down the middle, show a clear line of symmetry. Flowers, too, often display symmetrical petals. You can use these natural finds to make imprints, greetings cards, or creative designs.

Summary Table: Types of Symmetry Activities

Understanding symmetry helps us in art, design, mathematics, and also connects us to the patterns in everyday life. Whether folding paper, spotting symmetrical shapes, or creating tile patterns, you will continue to find symmetry present in many things around you.

Class 4 Maths Chapter 11 Notes – Fun with Symmetry Key Points for Quick Revision

These Class 4 Maths Chapter 11 notes provide clear explanations and easy examples of symmetry in nature and shapes. Students can quickly revise concepts like the line of symmetry, mirror images in numbers and letters, and creating patterns using tiles or paper folding. Practice activities make learning practical and fun.

Going through these NCERT revision notes will help students understand symmetry for both exams and everyday life. The notes cover all main activities—like making symmetrical patterns, cutting designs, and exploring symmetry outdoors—ensuring strong foundational learning in a simple manner.