Lesson Note on Algorithms and Flow Chart: Flowchart Symbols and Their Uses for SSS 2

Class: Senior Secondary School 2 (SS2 / SSS2)
Term: 3rd Term
Week: 3
Age: 16 years
Duration: 45 minutes
Subject: Computer Studies
Curriculum Theme: Problem Solving and Programming
Previous Lesson: Algorithm and Flow Chart: Writing Algorithms for Problem Solving.
Topic: ALGORITHMS AND FLOW CHART
Subject Matter: Flow chart symbols (input output, process, decision, start stop, connector), use of each flow chart symbol

Specific Objectives

By the end of the lesson, pupils should be able to:

Cognitive Domain:

• Identify various flowchart symbols.
• State the meaning and purpose of each flowchart symbol.
• Outline the steps involved in drawing a simple flowchart.

Affective Domain:

• Appreciate the importance of flowcharts in problem-solving.
• Show willingness to use flowcharts for representing algorithms.

Psychomotor Domain:

• Draw different flowchart symbols correctly.
• Construct a simple flowchart for a given problem.

Social Domain:

• Collaborate with peers to interpret and draw flowcharts.

Reference Materials

The following resources were used in planning this lesson:

• Senior Secondary Schools Education Curriculum
• State Unified Scheme of Work
• Oyewole, A. (2018). Comprehensive Computer Studies for Senior Secondary Schools. Learn Africa Publications.

Instructional Materials

The teacher will teach this lesson with the aid of:

• Flowchart symbols chart
• Graph sheet
• Marker
• Sample flowcharts

Rationale for the Lesson

This lesson helps pupils to visualize and understand the logical steps required to solve a problem using flowcharts. It enables them to design clear and structured solutions before writing computer programs, which is an important skill in computer science.

Prerequisite/Previous Knowledge

Pupils should have basic knowledge of algorithms and problem-solving concepts.

Lesson Content/Board Summary

Flowchart Symbols and Their Uses

Introduction to Flowcharts

A flowchart is a graphical representation of an algorithm or a step-by-step process. It uses various symbols to depict different types of actions or steps in a process, and arrows to show the flow of control.

Key Flowchart Symbols and Their Functions

The following are common flowchart symbols and their uses:

• Terminal Symbol (Start/Stop):

  This symbol is an oval or rounded rectangle. It marks the beginning (START) and the end (END) of a flowchart. Every flowchart must have one START and one END symbol.

• Input/Output Symbol:

  This symbol is a parallelogram. It represents any operation where data is entered into the program (input) or results are displayed (output).

• Process Symbol:

  This symbol is a rectangle. It represents any processing step, such as calculations, assignments, or data manipulation (e.g., SUM = A + B, X = Y * Z).

• Decision Symbol:

  This symbol is a diamond shape. It indicates a point where a decision is made, usually resulting in two possible paths (e.g., YES/NO, TRUE/FALSE). It has one entry point and two exit points.

• Connector Symbol:

  This symbol is a small circle. It is used to connect different parts of a flowchart, especially when the flowchart spans multiple pages or when connections are complex to avoid clutter.

• Flow Line:

  These are arrows that show the direction of flow or the sequence of operations in the flowchart. They connect the different symbols.

Example Flowchart: To calculate the sum of two numbers

(Imagine an oval symbol here for START)
START
    ↓
(Imagine a parallelogram symbol here for INPUT A)
INPUT A
    ↓
(Imagine a parallelogram symbol here for INPUT B)
INPUT B
    ↓
(Imagine a rectangle symbol here for SUM = A + B)
SUM = A + B
    ↓
(Imagine a parallelogram symbol here for OUTPUT SUM)
OUTPUT SUM
    ↓
(Imagine an oval symbol here for END)
END

Teaching Methods/Instructional Techniques

Discussion, Lecture, Demonstration, Question and Answer, Visual Aids

Instructional Procedures

Step 1: Introduction

Time: 5 minutes

Teaching Skill: Set Induction

Teacher’s Activity: The teacher asks pupils to recall what an algorithm is and its importance in problem-solving. The teacher then introduces flowcharts as another way to represent algorithms.

Pupils’ Activity: Pupils respond to the questions and listen attentively to the introduction.

Learning Point: Pupils recall algorithms and are introduced to flowcharts.

Step 2: Presentation of Flowchart Symbols

Time: 10 minutes

Teaching Skill: Explanation/Demonstration

Teacher’s Activity: The teacher displays a chart showing various flowchart symbols (terminal, input/output, process, decision, connector, flow line) and draws them on the board.

Pupils’ Activity: Pupils observe the symbols on the chart and as drawn on the board, copying them into their notes.

Learning Point: Pupils identify and recognize different flowchart symbols.

Step 3: Explanation of Symbol Uses

Time: 10 minutes

Teaching Skill: Explanation

Teacher’s Activity: The teacher explains the meaning and specific use of each flowchart symbol, providing simple examples for clarity.

Pupils’ Activity: Pupils listen, ask questions, and take notes on the function of each symbol.

Learning Point: Pupils understand the purpose and application of each flowchart symbol.

Step 4: Demonstration of Simple Flowchart

Time: 7 minutes

Teaching Skill: Demonstration

Teacher’s Activity: The teacher demonstrates how to draw a simple flowchart to solve a problem, such as calculating the sum of two numbers, using the symbols explained.

Pupils’ Activity: Pupils observe carefully and ask questions during the demonstration.

Learning Point: Pupils see a practical application of flowchart symbols in problem-solving.

Step 5: Guided Practice

Time: 5 minutes

Teaching Skill: Guided Practice

Teacher’s Activity: The teacher provides a simple problem (e.g., “Find the area of a rectangle”) and guides pupils to draw a flowchart for it on their graph sheets.

Pupils’ Activity: Pupils attempt to draw the flowchart for the given problem with the teacher’s guidance.

Learning Point: Pupils practice drawing flowcharts for simple problems.

Step 6: Class Discussion and Correction

Time: 5 minutes

Teaching Skill: Feedback/Correction

Teacher’s Activity: The teacher reviews some of the pupils’ drawn flowcharts, highlighting correct practices and making necessary corrections as a class.

Pupils’ Activity: Pupils participate in the discussion, compare their work, and make corrections.

Learning Point: Pupils receive feedback and improve their flowchart drawing skills.

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

1. List four common flowchart symbols.
2. What is the purpose of the decision symbol in a flowchart?
3. Draw the symbol used for input/output operations.
4. Briefly explain why flowcharts are useful in computer programming.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Pupils demonstrate understanding of the lesson.

Step 8: Conclusion

Time: 5 minutes

Teaching Skill: Summarization/Assignment

Teacher’s Activity: The teacher summarizes the key points of the lesson on flowchart symbols and assigns homework: “Draw a flowchart to convert temperature from Celsius to Fahrenheit.”

Pupils’ Activity: Pupils listen to the summary and copy the homework assignment.

Learning Point: Pupils consolidate their learning and are given an opportunity for further practice.

Lesson Keywords

• Flowchart – A graphical representation of an algorithm.
• Symbol – A distinct shape used in flowcharts to represent a specific operation.
• Terminal – The start or end of a flowchart.
• Input/Output – Operations for data entry or display of results.
• Process – An action or calculation step.
• Decision – A point where a choice is made, leading to different paths.
• Flow Line – An arrow showing the sequence of operations.

Differentiation

For pupils who grasp the concepts quickly, the teacher can provide more complex problems to design flowcharts for. For pupils needing more support, the teacher can provide partially completed flowcharts for them to finish or offer one-on-one guidance during practice sessions.

Note for teachers using this lesson plan

Ensure that the flowchart symbols drawn on the board are clear and proportional. Encourage pupils to use rulers and pencils to draw neat flowcharts. Emphasize the importance of clear labels within symbols and correct flow line directions. Provide opportunities for pupils to critique each other’s flowcharts constructively.