Yr 4 or 5 Scratch Drawing - CS and CT

Drawing shapes, patterns and pictures using Scratch

Created by Matthew Wimpenny - Smith
last edited Dec 03 2017 by Matthew Wimpenny - Smith

This project is an old favorite of mine. I always start with the question ‘how do you draw a square?’ Easy they say you get a ruler and draw four sides of equal lengths.

Question - ‘how would you program a robot to draw a square?’ Explain the need to develop a square drawing algorithm which is established by logical thinking and decomposition of the problem ‘how do you get a robot to draw a square’

After an unplugged activities using masking tape on the floor of the classroom and pupils becoming robots and algorithm is established in some form of notation such as a flow chart. Alongside teaching about steps and turns (90 degrees etc)

Question - ‘how do we turn the algorithm into Scratch coding blocks?’ Activity - Pupils go off into Scratch and start to create the code for drawing a square. Basic Square Algorithm

Question ‘Is this script the most efficient way to draw a square?’ discussion around abstraction and patterns. Leading to a discussion about the repeat block.

Activity Making the square script better using a repeat block.
Basic Square Drawing Using a Repeat

The next steps

Establish with the pupils the relationship between the number of repeats being related to the number of sides of the shape you are trying to draw. Then led the pupils onto the notion that number of sides divided by 360 degrees gives them the angle of the turn they need in Scratch to draw multi-sided shapes such as hexagons.

Activity Shape investigation creating a program that will investigate any multi-sided shape. Shape investigator program

The next step

Activity Now that you can draw shapes you can make patterns by repeating shapes. In the this code the shapes are created using more blocks which is like a function. Repeating patterns

The final step

Drawing a house. Explain that once you know how to draw shapes and repeat them you can draw pictures, just like this house

Many thanks @mwimpennys2017

Level: Lower - KS2

Duration: 1/2 Term (6-7 Lessons)

Teaches: CS and Computational Thinking