Turtle Snowflakes (with Python)
NOTE: A self-guided (in-browser) tutorial version of this lesson (suitable for remote / independent learning) can be found by here:
Turtle snowflake tutorial
Turtle snowflake tutorial
Learning Objectives:
Curriculum Mapping:
- Understand and use sequence in an algorithm
- Understand and use iteration in an algorithm (FOR and WHILE loops)
Curriculum Mapping:
KS2:
- Design, write and debug programs that accomplish specific goals; solve problems by breaking them into smaller parts. Select, use and combine a variety of software on a range of digital devices to design and create a range of programs.
- Use sequence, selection and repetition in programs; work with variables and various forms of input and output
- Use logical reasoning to explain how some simple algorithms work; detect and correct errors in algorithms and programs
KS3:
- Use two or more programming languages, at least one of which is textual, to solve a variety of computational problems.
STUDENT: COMPUTATIONAL THINKER:
- 5a: Students break problems into component parts, extract key information, and develop descriptive models to understand complex systems or facilitate problem-solving.
- 5c: Students break problems into component parts, extract key information, and develop descriptive models to understand complex systems or facilitate problem-solving.
- 5d: Students understand how automation works and use algorithmic thinking to develop a sequence of steps to create and test automated solutions.
EDUCATOR: COMPUTATIONAL THINKING COMPETENCIES:
- 4b: Design authentic learning activities that ask students to leverage a design process to solve problems with awareness of technical and human constraints and defend their design choices.
COMPUTER SCIENCE EDUCATORS:
- 2a: Plan and teach computer science lessons/units using effective and engaging practices and methodologies:
i. Select a variety of real-world computing problems and project-based methodologies that support active and authentic learning and provide opportunities for creative and innovative thinking and problem solving
ii. Demonstrate the use of a variety of collaborative groupings in lesson plans/units and assessments
iii. Design activities that require students to effectively describe computing artifacts and communicate results using multiple forms of media
iv. Develop lessons and methods that engage and empower learners from diverse cultural and linguistic backgrounds
v. Identify problematic concepts and constructs in computer science and appropriate strategies to address them
vi. Design and implement developmentally appropriate learning opportunities supporting the diverse needs of all learners
vii. Create and implement multiple forms of assessment and use resulting data to capture student learning, provide remediation and shape classroom instruction
CSTA K–12 CS Standards:
- 1B-AP-08: Compare and refine multiple algorithms for the same task and determine which is the most appropriate.
- 1B-AP-09: Create programs that use variables to store and modify data.
- 1B-AP-10: Create programs that include sequences, events, loops, and conditionals.
- 1B-AP-11: Decompose (break down) problems into smaller, manageable subproblems to facilitate the program development process.
- 1B-AP-13: Use an iterative process to plan the development of a program by including others' perspectives and considering user preferences.
- 1B-AP-15: Test and debug (identify and fix errors) a program or algorithm to ensure it runs as intended.
- 1B-AP-17: Describe choices made during program development using code comments, presentations, and demonstrations.
- 2-AP-11: Create clearly named variables that represent different data types and perform operations on their values
- 2-AP-12: Design and iteratively develop programs that combine control structures, including nested loops and compound conditionals.
- 2-AP-15: Seek and incorporate feedback from team members and users to refine a solution that meets user needs.
- 2-AP-16: Incorporate existing code, media, and libraries into original programs, and give attribution.
- 2-AP-17: Systematically test and refine programs using a range of test cases.
- 3A-AP-14: Use lists to simplify solutions, generalizing computational problems instead of repeatedly using simple variables.
- 3A-AP-15: Justify the selection of specific control structures when tradeoffs involve implementation, readability, and program performance, and explain the benefits and drawbacks of choices made.
AREA OF LEARNING AND EXPERIENCE: Science and Technology:
Computation is the foundation for our digital world.
Progression step 3
- I can use conditional statements to add control and decision-making to algorithms.
- I can identify repeating patterns and use loops to make my algorithms more concise.
- I can explain and debug algorithms.
Progression step 4
- I can decompose given problems and select appropriate constructs to express solutions in a variety of environments.
- I can select and use data structures that efficiently manage data in algorithms.
- I can plan and implement test strategies to identify errors in programs.
Progression step 5
- I can identify, define and decompose problems, choose appropriate constructs and express solutions in a variety of environments.
- I can use file-handling techniques to manipulate data in algorithms.
- I can test, evaluate and improve a solution in software.
In this lesson, students will create snowflakes using the turtle library in Python.
Part 1
Start by sharing the following code. Ask students to make a prediction about the output from the code.
Start by sharing the following code. Ask students to make a prediction about the output from the code.
Ask students to make a prediction about the output from the code.
Run the code and aks the students if their predictions were correct.
Go through each line of code (line-by-line) and explain what each line does.
import turtle - Imports the turtle library
window = turtle.Screen() - Creates a new blank canvas to draw on
timmy = turtle.Turtle() - Creates a new turtle called timmy
timmy.forward(100) - Move the turtle forward 100 steps
timmy.right(90) - Rotates the turtle right by 90 degrees
timmy.forward(100) - Move the turtle forward 100 steps
timmy.right(90) - Rotates the turtle right by 90 degrees
timmy.forward(100) - Move the turtle forward 100 steps
timmy.right(90) - Rotates the turtle right by 90 degrees
timmy.forward(100) - Move the turtle forward 100 steps
timmy.right(90) - Rotates the turtle right by 90 degrees
Challenge
Share the link to the code sample below and ask the students to modify their code to draw another regular polygon, e.g. triangle, hexagon etc.
Sample code:
https://trinket.io/python/ed15bdc4a6
Run the code and aks the students if their predictions were correct.
Go through each line of code (line-by-line) and explain what each line does.
import turtle - Imports the turtle library
window = turtle.Screen() - Creates a new blank canvas to draw on
timmy = turtle.Turtle() - Creates a new turtle called timmy
timmy.forward(100) - Move the turtle forward 100 steps
timmy.right(90) - Rotates the turtle right by 90 degrees
timmy.forward(100) - Move the turtle forward 100 steps
timmy.right(90) - Rotates the turtle right by 90 degrees
timmy.forward(100) - Move the turtle forward 100 steps
timmy.right(90) - Rotates the turtle right by 90 degrees
timmy.forward(100) - Move the turtle forward 100 steps
timmy.right(90) - Rotates the turtle right by 90 degrees
Challenge
Share the link to the code sample below and ask the students to modify their code to draw another regular polygon, e.g. triangle, hexagon etc.
Sample code:
https://trinket.io/python/ed15bdc4a6
Alternatively, share the following code via Teams / Google Classroom etc.
|
import turtle #Import the turtle library
window = turtle.Screen() #Create a new window timmy = turtle.Turtle() #Create a new turtle called timmy timmy.forward(100) timmy.right(90) timmy.forward(100) timmy.right(90) timmy.forward(100) timmy.right(90) timmy.forward(100) timmy.right(90) |
Part 2
Ask the students to identify the repeating pattern in the previous example. Answer: forward(100) + right(90) are repeated 4 times.
Ask students to suggest ways we can improve the code – draw out answers such as ‘use a loop’, ‘use a counted loop’, ‘use a repeat command’ etc.
Display the optimised solution for the previous example (see below) and have the students modify their own code to match the new solution.
Ask the students to identify the repeating pattern in the previous example. Answer: forward(100) + right(90) are repeated 4 times.
Ask students to suggest ways we can improve the code – draw out answers such as ‘use a loop’, ‘use a counted loop’, ‘use a repeat command’ etc.
Display the optimised solution for the previous example (see below) and have the students modify their own code to match the new solution.
Bonus Challenge
Time permitting, challenge the students to recreate one or more of the following shapes:
Time permitting, challenge the students to recreate one or more of the following shapes:
Helpful resources
| challenge_cards.pdf |
| angles_worksheet.pdf |
Part 3 - Snowflake Challenge
Share the following example:
Share the following example:
Challenge the students to guess the shape before running the sample code.
Explain to the students that they are going to use what they have learnt so far to draw a snowflake in Python.
Share the following worked example with the students and have them tinker with the code.
Worked example:
https://trinket.io/python/144a0d13f5
Explain to the students that they are going to use what they have learnt so far to draw a snowflake in Python.
Share the following worked example with the students and have them tinker with the code.
Worked example:
https://trinket.io/python/144a0d13f5
|
import turtle #This imports the turtle library
window = turtle.Screen() #This creates a new window timmy = turtle.Turtle() #This creates a new turtle called timmy for loopCounter in range(4): #Change the number of iterations for loopCounter in range(2): timmy.forward(100) timmy.right(60) timmy.forward(100) timmy.right(120) timmy.right(90) #Change the angle |
Challenge
Challenge the class to see who can create the best snowflake.
Challenge the class to see who can create the best snowflake.
Top tip: The last rotation (which in the above example 90 is degrees) can be calculated by dividing 360 degrees by the first 'repeat' value.
For example, if the first repeat is 6 then the last turn should be 360 / 6 = 60. Try it! :)
Advanced Snowflake
For example, if the first repeat is 6 then the last turn should be 360 / 6 = 60. Try it! :)
Advanced Snowflake
Plenary
- Direct students to: https://www.teachwithict.com/let-it-snow.html
- Instruct students to copy and paste their Python snowflake code into the simulator
Strategies for Student Engagement
- Encourage predictions and discussions to involve students actively in the learning process.
- Provide hands-on practice with immediate feedback to reinforce learning.
- Use visual aids (projector/whiteboard) to demonstrate concepts clearly.
- Offer challenges and competitions to motivate students and foster a sense of achievement.
Assessment Criteria
Student "I can" checklist
Part 1: The Basics (Sequence)
Student "I can" checklist
Part 1: The Basics (Sequence)
- [ ] I can import the turtle library.
- [ ] I can make the turtle move forward and turn at specific angles.
- [ ] I can draw a simple shape (like a square) by writing a list of instructions.
- [ ] I can identify lines of code that are being repeated.
- [ ] I can use a for loop to repeat code (e.g., for i in range(4):).
- [ ] I can draw a square or triangle using only 3-4 lines of code inside a loop.
- [ ] I can put one loop inside another loop (nested loop).
- [ ] I can can create a complex snowflake shape using nested loops.
- [ ] I have created a snowflake that is fully symmetrical.
- [ ] I have defined a function (e.g., def draw_snowflake():) to organise my code.
- [ ] I use random numbers to change the size, colour, or position of my snowflakes.
- [ ] I have added comments (#) to explain what my code does.
You may also be interested in:
Tags: programming language scratch, scratch programming language, scratch coding language, programming languages scratch, scratch code language, scratch programming language.