Unplugged Coding Lesson – Exploring Functions in Computer Science

Lesson on functions in computer science programming



Students will understand the basic concept of functions in programming through an engaging, hands-on activity that does not require computers. They will learn how functions can perform specific tasks and how they can be used to simplify coding processes.

Materials Needed

  • Large sheets of paper or poster boards
  • Markers or crayons
  • A set of instruction cards (prepared in advance) with simple, fun actions written on them (e.g., “Clap your hands”, “Spin around”, “Jump up”)
  • A “Function Box” – a large box or designated area marked as the function zone
  • Small rewards or stickers for participation

Lesson Duration

45 minutes

Lesson Overview

This lesson introduces the concept of functions in coding through an interactive activity. By using physical actions as analogs for coding tasks, students will grasp how functions work to perform specific actions and how they can make repetitive tasks more efficient.

Introduction to Functions (5 minutes)

Start by explaining what a function is in simple terms:

  • A function in programming is like a magic box that does something special every time you use it. You give it something, and it gives you back something different after doing its magic.

Warm-up Activity: Simon Says Function Game (10 minutes)

  • Play a modified version of “Simon Says” to introduce the idea of following specific commands (functions).
  • Explain that when you say “Function says clap your hands,” they need to perform the action. If the command doesn’t start with “Function says,” they should not perform the action.
  • This activity illustrates the concept of calling a function to perform a task.

Creating Our First Functions (10 minutes)

  • Activity Setup:
  • Place the “Function Box” in a visible area of the classroom.
  • Spread the instruction cards face down around the room.
  • Activity Instructions:
  • Divide the students into small groups.
  • Each group picks an instruction card and decides on a fun name for their function (e.g., “The Clapper” for clapping hands).
  • Groups take turns presenting their function: They announce the function name, perform the action written on their card inside the “Function Box,” and explain that anytime someone calls their function (says the name), they’ll perform the action.

Group Activity: Function Chain (15 minutes)

  • Activity Setup:
  • Each group writes their function name on a large sheet of paper and draws a simple symbol or picture representing their action.
  • Activity Instructions:
  • Groups line up, holding their function sheet in front of them.
  • The first group performs their function by calling its name and doing the action.
  • The next group in line calls their function, performs their action, and then calls the next group’s function.
  • Continue until all groups have performed their functions in sequence, creating a “function chain” that illustrates how functions can be called in order to perform tasks.

Reflection and Discussion (5 minutes)

  • Discuss how functions made it easier to perform and remember the actions.
  • Ask students how they think functions might help in coding and computer science.


This lesson plan offers a foundational understanding of functions in coding through an interactive and playful approach. By creating and calling their own “functions,” students learn how these coding elements can simplify tasks and sequences, an essential concept in programming. Encourage students to think of other actions or tasks that could be turned into functions for even more fun and learning.


IDE options


16 Apr 2024

Ready to Boost Your Teen’s Future with Coding?

Best dev enviroments for learning to code


16 Apr 2024

Top 5 Epic Coding Environments for Teens

review kids coding sites

Education, Learn to Code

16 Apr 2024

Top Learn-to-Code Online Sites and Tools for Kids

Convert USD to other currency program

Advanced Placement, Java, Tutorial

4 Apr 2024

Object-Oriented Programming in Java – AP CS A

learn to use replit IDE

Advanced Placement, Java, Tutorial

4 Apr 2024

Exploring Concurrency in Java – AP Exam

Minecraft Mods in Java


4 Apr 2024

Getting Started with Minecraft Forge

Lesson on functions in computer science programming


4 Apr 2024

Preparing to Teach Coding for the First Time

learn to code as a family


4 Apr 2024

In-Person vs. Live Virtual Coding Lessons