Minecraft Education – Lesson 3

Objectives

• Create chat commands that trigger Python code.
• Use if-statements to make decisions.
• Control behavior based on user input or simple conditions.

Vocabulary

• Event – Something that happens (like typing a chat command) that triggers code.
• Conditional (if-statement) – Runs code only if a condition is true.

Part A – Simple Chat Command

We can attach code to a word we type in the chat.

Sample Code:

def on_chat():
    player.say("You used the 'start' command!")

player.on_chat("start", on_chat)

Try: Type start in the game chat and see the message appear.

Part B – Conditionals (If-Statements)

We can make choices in our code using if and else.

Sample Code:

health = 10  # pretend health value for this example

if health > 5:
    player.say("You are healthy!")
else:
    player.say("You need healing!")

Discussion:

• health > 5 is a Boolean condition (true or false).
• The if block runs when the condition is true.
• The else block runs otherwise.

Part C – Chat Command That Builds Different Structures

Here we use a chat command and a conditional to choose between different builds.

Sample Code:

def build_structure(struct_type):
    if struct_type == 1:
        player.say("Building a stone tower!")
        for y in range(5):
            blocks.place(STONE, pos(0, y, 0))
    else:
        player.say("Building a glass pillar!")
        for y in range(5):
            blocks.place(GLASS, pos(0, y, 0))

def on_chat_type(num):
    build_structure(num)

player.on_chat_number("build", on_chat_type)

Usage:

• Type build 1 in chat → builds a stone tower.
• Type build 2 in chat → builds a glass pillar.

(If your Python template does not support numeric chat parameters in this way, you can simplify to one structure per command such as "tower" and "pillar".)

Exit Ticket / Reflection

• In your own words, what does an if-statement do?
• How did using chat commands make your program feel interactive?