**Lesson Plan: Straight Line Graphs**
**Grade Level:** Senior Secondary 2 (SS2)
**Subject:** Mathematics
**Duration:** 60 minutes
**Lesson Topic:** Straight Line Graphs
**Objective:**
By the end of the lesson, students will be able to:
1. Identify and understand the standard form of a straight line equation (y = mx + c).
2. Calculate the slope (m) and y-intercept (c) of a straight line.
3. Plot straight lines on a graph using a given equation.
4. Interpret the relationship between two linear graphs.
**Materials Needed:**
- Whiteboard and markers
- Graph paper
- Rulers
- Scientific calculators
- Projector (optional for visual aids)
**Lesson Structure:**
**Introduction (10 minutes):**
1. **Greeting and Attendance** (2 minutes)
- Greet students and take attendance.
2. **Hook** (3 minutes)
- Introduce the topic by relating it to real-life scenarios (e.g., movements of elevators, financial growth over time).
3. **Objective Setting** (5 minutes)
- Explain the goals of today’s lesson.
- Quick pre-assessment question: "What do you remember about coordinates and basic graphing principles?" to gauge prior knowledge.
**Body (40 minutes):**
1. **Introduction to the Equation of a Straight Line** (10 minutes)
- Write the equation y = mx + c on the board.
- Explain that “m” represents the slope of the line and “c” represents the y-intercept.
- Provide examples and counterexamples illustrating different slopes and intercepts.
2. **Calculating Slope and Y-Intercept** (10 minutes)
- Show how to calculate the slope (m) as the change in y divided by the change in x (rise/run).
- Demonstrate how to identify the y-intercept (c) where the line crosses the y-axis.
- Solve sample problems with the class.
3. **Graphing Straight Line Equations** (15 minutes)
- Distribute graph paper and rulers to students.
- Lead the students through plotting a straight line using a given equation, y = 2x + 3.
- Guide students to plot at least two points (e.g., for x=0 and x=2) and draw the line.
- Allow students to practice with another equation, y = -x + 1.
4. **Interpreting Relationships Between Lines** (5 minutes)
- Discuss parallel lines (same slope, different y-intercepts).
- Discuss perpendicular lines (slopes are negative reciprocals).
**Conclusion (10 minutes):**
1. **Review and Summarize** (5 minutes)
- Summarize key points: standard form equation, calculating slope and intercept, and graphing.
2. **Questions and Answers** (5 minutes)
- Open the floor for any questions from students.
- Clarify any misconceptions.
3. **Assignment**
- Assign homework to practice four additional straight-line equations, plot them, and label the slope and y-intercept.
**Assessment:**
- Formative assessment through observation and in-class practice.
- Summative assessment via the homework assignment.
**Reflection:**
- After the lesson, reflect on what went well and areas for improvement.
- Note any particular difficulties encountered by students and plan for additional support sessions if needed.