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How to run a turtle program online

Here is a short program worth running first. It draws a five-pointed star:

import turtle

t = turtle.Turtle()
for i in range(5):
    t.forward(150)
    t.right(144)

Each pass through the loop moves the turtle forward 150 steps and turns it 144 degrees. Five turns of 144 degrees add up to 720, two full circles, which is why the lines cross and make a star.

The buttons under the drawing replay it: Step goes one move at a time, and Slow, Medium, Fast and Instant set the pace. If a command is misspelled, CodeGrove says so and suggests the one you probably meant.

Five turtle programs to try

Each one opens in CodeGrove with the code already typed in. Press Run to watch it draw, then change a number and run it again.

A five-pointed star

import turtle

t = turtle.Turtle()
for i in range(5):
    t.forward(150)
    t.right(144)

Open in CodeGrove

Try this: change 144 to 160 and range(5) to range(9) for a nine-pointed star.

A square spiral

import turtle

t = turtle.Turtle()
t.speed(0)
for i in range(60):
    t.forward(i * 5)
    t.right(90)

Open in CodeGrove

Each side is 5 steps longer than the one before, so the square never closes. Try this: turn 91 degrees instead of 90.

A flower of circles

import turtle

t = turtle.Turtle()
t.color("crimson")
for i in range(12):
    t.circle(60)
    t.right(30)

Open in CodeGrove

Twelve turns of 30 degrees make one full turn. Try this: draw 36 circles and turn 10 degrees each time.

A color spiral

import turtle

t = turtle.Turtle()
colors = ["red", "orange", "gold",
          "green", "blue", "purple"]
for i in range(72):
    t.pencolor(colors[i % 6])
    t.forward(i * 3)
    t.left(59)

Open in CodeGrove

i % 6 picks the next of the six colors on every pass. Try this: turn 61 degrees instead of 59.

A house with a filled roof

import turtle

t = turtle.Turtle()
t.fillcolor("tan")
t.begin_fill()
for i in range(4):
    t.forward(120)
    t.left(90)
t.end_fill()

t.left(90)
t.forward(120)
t.right(90)
t.fillcolor("firebrick")
t.begin_fill()
for i in range(3):
    t.forward(120)
    t.left(120)
t.end_fill()

Open in CodeGrove

begin_fill() and end_fill() color in the shape drawn between them. Try this: add a door with a smaller filled rectangle.

Turtle commands CodeGrove knows

CodeGrove's turtle follows Python's own turtle module, so most code from a textbook or a worksheet runs as written. These are the commands students use most:

A program can make up to 20,000 moves. Keyboard and mouse events such as onkey and onclick are not supported yet.

Turtle in a Python class

CodeGrove is the code lab for our two Python courses, and Python Programming 2 has turtle drawing tasks that CodeGrove checks for the student, from shapes in Unit 1 to a forest fire simulation in Unit 6. Any teacher can use the editor itself for free, with their own programs.

To hand a turtle program to a class, open it in CodeGrove, press Share, then Copy link, and post the link. The guide for teachers covers collecting the work and checking a whole class at once.

Common questions

More about CodeGrove