Lecture 2 — Turtle Pen Control & Movements⌗

Instructor: Laksh Budhrani

Review / Recap⌗

Basic Commands from Lecture 1⌗

Objectives⌗

1. Understand penup() and pendown()
2. Learn how to turn using right(angle)
3. Learn how to move backward using backward(distance)

Objective 1 — penup() and pendown()⌗

Simple Definitions⌗

• penup() — Move the turtle without drawing.
• pendown() — Put the pen down to start drawing again.

Example: Drawing Three Horizontal Lines⌗

import turtle as trtl

p = trtl.Turtle()

# --- ENTER YOUR CODE HERE ---
p.forward(50)
p.penup()

p.forward(50)
p.pendown()

p.forward(50)
# --------------------------------------------------------------
# (Stop writing code above this line)

wn = trtl.Screen()
wn.mainloop()

Objective 2 & 3 — right() and backward()⌗

Simple Definitions⌗

• right(angle) — Turn the turtle clockwise by the given angle.
• backward(distance) — Move the turtle straight backward without turning.

Example: Drawing a Simple Letter C⌗

import turtle as trtl

p = trtl.Turtle()

# --- ENTER YOUR CODE HERE ---
p.backward(70)
p.right(90)

p.forward(120)
p.left(90)

p.forward(70)
# --------------------------------------------------------------
# (Stop writing code above this line)

wn = trtl.Screen()
wn.mainloop()

House Drawing Activity (Guided)⌗

Create a new Python file in VS Code named:
turtle_class2.py

House Image⌗

Explain in Plain English⌗

Write a short explanation (3–5 sentences) describing how you think we can draw this house using:

• forward()
• left()
• right()
• backward()
• penup()
• pendown()

Explain the steps in simple English, as if you are telling a friend how to draw it.

Boilerplate Code⌗

import turtle as trtl

p = trtl.Turtle()
p.speed(0)

# --- ENTER YOUR CODE HERE ---
# (Write your house drawing steps using the new commands)



# --------------------------------------------------------------
# (Stop writing code above this line)

wn = trtl.Screen()
wn.mainloop()

Notes⌗

• Use penup() to move without drawing.
• Use pendown() to start drawing again.
• Use right() for clockwise turns.
• Use backward() if you need to reverse a little.

Independent Activity — Letter L Inside a Square⌗

Letter L Image⌗

Your Task⌗

Look at the image above and draw it independently using:

• forward(distance)
• left(angle)
• right(angle)
• backward(distance)
• penup()
• pendown()

Use the Turtle boilerplate code provided earlier in this lecture.

Create Your Own File⌗

Create a new Python file in VS Code named:

turtle_class2_independent.py

Inside that file, use the boilerplate and write your letter‑drawing code in the section marked:

# --- ENTER YOUR CODE HERE ---

Submission Instructions⌗

Submit your work in Google Classroom by:

1. Creating a Google Doc
2. Pasting your code into the document
3. Adding a screenshot of the output window showing your drawing
4. Turn in the Google Doc to the assignment titled In‑Class Exercise 2