Scratch pen polygons maths mission
A practical mini-mission using pen polygons to practise angles through questions, examples and child-friendly challenges.
Quick answer
When you use the pen to draw polygons in Scratch, you can learn about angles by turning your sprite at specific degrees for each side. By following a pattern of turning and moving, you can create shapes like triangles, squares, and hexagons.
Learning outcome
By the end of this page, you will be able to draw regular polygons in Scratch by turning your sprite at the correct angles and moving forward the same distance for each side.
- You can explain how to calculate the turning angle for any regular polygon
- You can draw at least three different polygons using Scratch pen
- You can predict how many sides a polygon will have based on turning angles
- You can use your knowledge to create a polygon with any number of sides
Why this matters
Learning about angles through Scratch helps you understand how shapes are built and how to create them using code. This skill is useful in games, art, and design. It also helps you think logically and solve problems by breaking down complex shapes into simple steps. When you know how to turn at the right angles, you can build any regular polygon – from a triangle to a dodecagon (12-sided shape)!
How it works
When you draw a polygon in Scratch using the pen, you need to:
- Move forward a fixed distance
- Turn by a specific angle
- Repeat these steps for the number of sides
The key is knowing how much to turn. For regular polygons, the turning angle is always 360° divided by the number of sides.
Examples you can see
Let's look at how to draw a square:
- Move forward 100 steps
- Turn right 90°
- Repeat 4 times
Why 90°? Because 360° ÷ 4 = 90°
Here’s a table showing how to draw regular polygons:
| Shape | Sides | Turning Angle |
|---|---|---|
| Triangle | 3 | 120° |
| Square | 4 | 90° |
| Pentagon | 5 | 72° |
| Hexagon | 6 | 60° |
| Heptagon | 7 | 51.43° |
| Octagon | 8 | 45° |
Try it as a mini adventure
Imagine you are a space explorer on a mission to draw the perfect alien shapes! Your spaceship has a special pen that draws polygons in the air. To complete your mission, you must:
- Draw a triangle with sides of 100 steps
- Draw a square with sides of 100 steps
- Draw a pentagon with sides of 100 steps
- Draw a hexagon with sides of 100 steps
- Draw a heptagon with sides of 100 steps
Each time, you must calculate the correct turning angle using the formula: 360° ÷ number of sides
Common mistakes
- Mistake: Forgetting to turn at the right angle and just moving in a straight line
- Why it happens: Not understanding that the turning angle is the same for all sides
- Fix: Remember to always turn by the correct angle (360° ÷ number of sides)
- Mistake: Using the wrong number of sides when calculating angles
- Why it happens: Confusing the number of sides with the number of turns
- Fix: Count the sides carefully and remember to turn after each side
- Mistake: Drawing shapes with different-sized sides
- Why it happens: Thinking that polygons can have different side lengths
- Fix: Keep the move forward distance the same for all sides
Parent and carer guide
Help your child understand the mission by:
- Using a ruler and protractor to demonstrate angles
- Creating a chart of different polygons and their angles
- Practising the formula together: 360° ÷ number of sides
- Using physical shapes like cut-out triangles and squares to show how angles work
- Encouraging your child to draw shapes on paper first before using Scratch
- Checking that they are turning the correct number of times
- Letting them experiment with different side lengths and numbers of sides
Remember, the key is to turn by the same angle each time. If they make a mistake, help them figure out what went wrong and how to correct it.
Practice questions
- What turning angle do you need to draw a hexagon?
- How many sides does a polygon have if it turns 60° each time?
- What is the turning angle for a pentagon?
- If you want to draw a shape with 10 sides, what angle should you turn?
- How many degrees must you turn to draw a triangle?
Answers:
- 60° (360° ÷ 6)
- 6 sides (360° ÷ 60°)
- 72° (360° ÷ 5)
- 36° (360° ÷ 10)
- 120° (360° ÷ 3)
FAQ
What is a polygon?
A polygon is a flat shape with straight sides. Examples include triangles, squares, pentagons, and hexagons.
Why do we turn 360° divided by the number of sides?
Because all the angles of a polygon add up to 360°. When you turn at each corner, you make a full circle.
Can I draw irregular polygons in Scratch?
Yes, but the angles won't be the same for each side. This mission focuses on regular polygons where all sides and angles are equal.
How do I know which way to turn?
It doesn't matter which direction you turn as long as you turn the same way each time. You can turn left or right.
Can I make my polygons bigger or smaller?
Yes! Change the number of steps you move forward to make the sides longer or shorter. The angles stay the same.