Peter Muller

Algebra I

Second Period

50 minute lesson

Warm Up:

    A graphing problem

Objectives:

    The students will distinguish between positive and negative slope

    The students will calculate the slope of various lines

    The students will identify and generate perpendicular and parallel lines base on their slope

    The students will calculate slope based on two given points

    The students will interpret slope intercept form

Materials:

    dry erase markers, vis-a-vis pens, transparencies.

Set:

    If you are driving down the road and see a sign that says steep grade ahead, trucks use lower gear.  I was on one the other day and I had to stop but the sign said it was a 6% grade, and there was a truck coming down behind me, I pulled over to the side to let that truck go rumbling by so it didn't take out the trunk of my car.  

    I will then describe 6% means 6 feet change over 100 feet, and say we are talking about slope today.

Procedures:

    I will introduce slope as rise over run.  and do an example on the board.  I will then ask one student to rise from his/her desk and run to the door.  I will then ask another student to run to the door and then rise from his/her desk.  I will ask them which is easier as a memory tool.

    Do a series of problems on the board of showing graphs and having students calculate the slope.   Followed by a series of guided practice slope problems.  some of the last guided practice problems will have zero slope and undefined slope.  I will then go through how to solve these with overhead notes.

    Point out that change in y equals rise, change in x equals run: y2-y1/x2-x1= m.  I will then guide the students through a number of examples where I give them two points and they calculate the slope.

    Introduce slope intercept form on the overhead, do a number of examples.

    If there is time I will introduce perpendicular and parallel lines.  I will ask the students if the know what they are.  I will then demonstrate how to identify them based on their slope.  

Closure:  To recap, rise over run, have a student demonstrate run over rise again.  y2-y1/x2-x1= m and slope intercept form is y = mx + b.  Ask students how to identify parallel and perpendicular lines.

    HW pg 403 # 14-21

Assessment/Evaluation:

    Informal:  I will judge students through answers to my questions and by their answers during guided practice.  

    Formal: Students will take a test that will include a section on slopes on Friday