9th Grade Algebra 1 Lesson Plan

Date: March 12, 2008, period 2

Classroom: F-209

Instructor: E. Reiss

Planning Team:

M. Boorman, D. Hafner E. Reiss, C. Tellez,

Z. Yahaya

Teacher: Akane Hiro

Title of the Lesson: Perpendicular Lines

Goals of the Lesson:

A.) Describe the relationship between the slopes of perpendicular lines.

B.) Use knowledge of the slopes of perpendicular lines to write equations

C.) Communicate ideas/conjectures through presentation

Back ground and Rationale for teaching this lesson:

Now that students have knowledge of variables, linear equations, and how to solve for these variables, it is time for them to move on to higher level applications. Graphs are a very useful tool in mathematics and also in real-life applications. It is important for every individual to have a concrete understanding of how to graph linear equations as well as how to find the equations of lines perpendicular to a given situation especially as it pertains to the NJ HSPA. Also, several “real-life” applications utilize the concept of perpendicular lines (engineering, construction/carpentry, graphic arts, etc). Lastly, as students present their ideas or as they check their peers’ presentations helps facilitate deep understanding of concepts.

Process of the Lesson:

Student Activities, Teacher’s Questions and Anticipated Student Reactions / Teacher Support and Things to Remember / Points of Evaluation
1. Accessing Prior Knowledge ( 1 min.)
Do Now: Write the Slope-Intercept Form of a linear equation
Ask: “What does m represent? What does b represent?” / Write the “Do Now” on the board before class begins / Do all students remember the Slope-Intercept form of a linear equation?
Do students have an understanding of what m and b represent?
2. Posing & Solving the Problem ( 10 min.)
Working in groups, students will complete Ex 1 from the Section 5.6 worksheet (attached)
If students are still utilizing “rise over run” to identify the slope of a line, discourage this method and reinforce identifying the slope by using Slope-Intercept Form from the equation given
The “recorder” will transfer one response onto the Presentation Poster Paper and tape it to the board / Distribute a worksheet, ruler, and protractor to each student.
Distribute 1 presentation poster paper, marker and ruler to the “recorder”.
Distribute a directions list to the “presenter”. / Are students having trouble using a protractor properly?
Are students identifying slope and y-intercepts correctly?
3. Presentations & Discussions ( 20 min.)
The “presenter” from each group will present their graph along with the slope, y-intercept, and equation of the perpendicular line they created.
After all groups have presented ask, “What is the relationship between the slope of the perpendicular line and your original line? Is there a relationship between the y-intercepts?”
Summarize your findings: If your friend was absent today, how would you explain the relationship between equations of perpendicular lines?
Copy the summary/definition/description at the bottom of your worksheet / Make sure students are facing their peers and speaking clearly.
Ask students if they agree with the findings presented. If they disagree, ask them to explain why.
Provide each group with a pre-sealed envelope with a formal definition/description of the equations of perpendicular lines / Can students clearly verbalize their findings in the written work?
Do students recognize that the slopes of the perpendicular lines are negative reciprocals of the original line?
Do students recognize that there is no relationship between the y-intercepts?
4. Student Practice ( 5 min.)
Students will now complete the reverse side of the Section 5.6 worksheet (attached).
Tell students to compare their answer with their group. / Make sure students are using the findings that were just presented.
Assist students who are having trouble “verifying” their graphs on the calculator. / Did students use the summary/definition/description of perpendicular lines to answer the practice problem?
5. Summary & Closure ( 4 min.)
Teacher will summarize the lesson.
Have students complete “Today I learned ... ” in their notebooks.
Assign homework / Teacher utilizes experiences from the activity as well as students’ presentations to summarize the main idea and close the lesson.
Remind students not to copy from the worksheet, but to complete the sentence in their own words. / Do students’ sentences and homework assignment demonstrate understanding of perpendicular lines?

Evaluation of the Lesson:

·  Was each student engaged with the activity?

·  Were students able to describe the relationship between the slopes of perpendicular lines?

·  Were students able to use knowledge of the slopes of perpendicular lines to write equations?

·  Were students able to communicate ideas/conjectures through presentation?

Extension:

As a follow-up activity, you may ask students to create a “memory game” on index cards where 2 equations whose lines are perpendicular would be a “match”. Each student creates 5 sets of equations. They may break into pairs, shuffle their cards, and play their game!

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