Your Guide to Teaching Algorithms in Computer Programming

By Trilby Hillenbrand

Are your students struggling to grasp the concept of algorithms in computer programming? This comprehensive guide provides practical strategies and resources to effectively teach this crucial subject, whether you’re a seasoned STEM teacher or just starting. We’ll explore how to break down complex algorithms into manageable steps, engage students in hands-on activities, and foster a deep understanding of this fundamental programming concept. 

Short on time? Grab a complete lesson on writing computer algorithms here.

Why Teaching Algorithms is Crucial in Computer Programming

Algorithms are the cornerstone of computer programming. They provide a step-by-step blueprint for solving problems, enabling computers to execute tasks. By learning to design and analyze algorithms, students develop:

• Computational Thinking: Essential for problem-solving in various fields, not just computer science.
• Logical Reasoning: Students learn to break down complex issues into smaller, more manageable steps.
• Coding Proficiency: A strong foundation in algorithms is crucial for understanding and writing effective code in any programming language.

Understanding the Basics of Algorithms

At its core, an algorithm is a step-by-step procedure that, when followed, leads to a specific outcome. Think of it as a recipe but for solving a problem or completing a task within a computer program. Key characteristics of an algorithm in computer programming include:

• Clear: The steps are unambiguous and easy to understand. Each instruction should be expressed in a way that leaves no room for misinterpretation.
• Simple: Each step should be relatively straightforward and easy to execute. Complex tasks should be broken down into smaller, more manageable steps.
• List format: Algorithms are typically presented in a step-by-step list or a similar structured format. This helps ensure the instructions are followed in the correct order.
• Sequential: The steps must be performed in a specific order to achieve the desired outcome. Changing the order of the steps may result in an incorrect or unexpected result.

In the context of computer programming, the algorithm serves as a blueprint for the code. Before writing a single line of code, programmers carefully design algorithms to outline the logical steps required to solve a particular problem. This process involves breaking down the problem into smaller, more management parts and then determining the sequence of steps necessary to achieve the desired outcome. Algorithms can be expressed in various forms, such as natural language, pseudocode, or flowcharts. 

For example, let’s say a robot needs to navigate a simple maze.

1. Start at the beginning of the maze.
2. Check if there is an open path to the right.
   • If yes, move right
   • If no, check if there is an open path forward.
     • If yes, move forward.
     • If no, check if there is an open path to the left.
       • If yes, move left.
       • If no, the robot is blocked and cannot proceed.
3. Repeat step 2 until the robot reaches the end of the maze. 
4. End.

This example demonstrates how an algorithm can be used to guide a “robot” through a series of decisions to reach a specific goal. This type of decision-making is fundamental to how computers solve problems.

Strategies for Engaging Students in Learning Algorithms

Engaging students in learning algorithms can be a challenging task, but implementing interactive and hands-on activities can significantly enhance their understanding and retention of the material.

Here are some activities you use to teach students about algorithms: 

1. Code the Teacher

• Activity: Emphasize the importance of clear and precise instructions and introduce the concept of “debugging” by identifying and correcting errors in the instructions.
• Preparation: Choose simple tasks with clear steps, such as making a sandwich, brushing teeth, or tying shoes.
• Variations:
  • Have students act as the “computer” and follow instructions written by their peers.
  • Introduce the concept of “subroutines” by breaking down complex tasks into smaller, more manageable sub-tasks with their own sets of instructions.

2. Directed Drawings

• Activity: Reinforce the importance of clear and concise instructions and the need to consider the perspective of the “receiver” when writing the algorithm.
• Preparation: Provide simple shapes or symbols as starting points.
• Variations:
  • Have students create drawings with increasing complexity.
  • Introduce the concept of loops by having students repeat certain steps in their instructions.

3. Flowcharting Recipes

• Activity: Introduce the concept of flowcharts as a visual representation of algorithms.
• Preparation: Choose simple recipes with a limited number of steps.
• Variations:
  • Use different symbols to represent different actions in the flowchart (e.g., ovals for start/end, rectangles for actions, diamonds for decisions).
  • Have students create flowcharts for other procedures, such as getting ready for school or brushing their teeth.

4. The Maze Game

• Activity: Introduce the concept of decision-making and conditional statements (if-then-else) in the context of an algorithm.
• Preparation: Create simple mazes with clear paths and obstacles.
• Variations:
  • Use different colored paths to represent different conditions.
  • Introduce the concept of loops by having the robot repeat a set of instructions.

5. Dance Algorithm

• Activity: Introduce the concept of loops (repetition) in a fun and engaging way.
• Preparation: Play upbeat music to accompany the dance routines.
• Variations:
  • Introduce the concept of nested loops (loops within loops) for more advanced students.
  • Have students create and perform their own dance routines.

6. Treasure Hunt

• Activity: Apply algorithmic thinking to a real-world scenario.
• Preparation: Hide a small “treasure” in the classroom. Have students write an algorithm to help a “treasure hunter” discover the treasure.
• Variations:
  • Increase the complexity of the treasure hunt by adding more obstacles.
  • Have students choose different items in the classroom for their “treasure” and create algorithms to help their classmates discover their unique treasure.

7. Building with Blocks:

• Activity: Emphasize the importance of clear and precise instructions and the need for accurate execution.
• Preparation: Provide a variety of building blocks (LEGOs, construction toys).
• Variations:
  • Have students create increasingly complex structures.
  • Introduce the concept of sub-assemblies by having students build smaller components of a larger structure.

Common Challenges in Teaching Algorithms and How to Overcome Them

There are several common challenges when teaching algorithms. 

• Visualization
  • Challenge: Due to the abstract nature of the subject, many students struggle to visualize how an algorithm works. 
  • Solution: Use unplugged coding or interactive digital tools that simulate algorithm execution. For example, in the “Maze Game” describe above, students can see how each step of the written algorithm corresponds to a move the object makes in the maze. 
• Complexity
  • Challenge: Students may become discouraged or overwhelmed when faced with lengthier algorithms. 
  • Solution: Break down algorithms into smaller, more manageable components. Encourage students to create and test one part of the algorithm at a time, gradually building up to the complete solution. For example, rather than writing an algorithm for a toy car to complete a maze, write an algorithm for the first 3 steps. Then test it and add on the next 3 moves.
• Translating to a Programming Language
  • Challenge: Students struggle with translating their algorithm to a programming language. 
  • Solution: Provide students with an anchor chart or handout with commonly used statements. Also, encourage students to move toward writing algorithms in psuedocode to provide additional practice and support with using the programming language. Consider starting with a visual programming language that allows students to drag and drop blocks of code rather than typing individual lines of code.

Need More Support Teaching Algorithms?

In this complete lesson, students will define algorithms and learn to write effective algorithms through engaging activities.

The computer algorithms lesson starts with a fun exploration where students write instructions for their “robot” teacher to follow. Then, they gather algorithm facts from an instructional video and fine-tune their algorithm writing skills in a partner activity. 

Learn More on TPT

Let’s get coding!

By incorporating these strategies and engaging activities, you can effectively teach your students the fundamentals of computer programming. This knowledge will empower them to become proficient programmers and develop essential critical thinking and problem-solving skills.