Lesson Plan

Slope-Definition, Values, and Finding

FIRST THING IS TO HANDOUT SLOPE WORKSHEET.

Strategy 1

                1.  Introduction

                A.  Welcome the class today and make a joke. (You guys look exhausted, I can not imagine why?)
                B.  Tell what we are doing today: 1) Inspecting what values are possible for the slope of a line and
                                                                   2) defining what the slope of a line tells us. (How steep the line is)
                C.  Instructional Objectives: The student will be able to

                                    1.  Describe which lines have a negative, positive, undefined, or zero slope.
                                    2.  Recognize that a slope measures the steepness of a line.

                2.  Activity
 
                A.  Ask the question "Can anyone take a guess what the possible values of a slope might be?"
                      Now that we have some guesses we are going use Geometer’s Sketchpad to see if we can find the possible
                      values of slope. Before we get started I want to break you into groups and review what we want to get
                      accomplished when we work in groups.
                 B.  Break the students into groups of two or three (in this case). When we break up into groups our purpose is to:

                                      1.  Use each other’s insights and ideas to collectively solve the problem.
                                      2.  I want you on task. This is not a time to talk about plans for the weekend.

                 C.  Open Geometer’s Sketchpad and show an example of how to find the slope of a line
                       (SHOW VERTICAL LINE). You need to sketch at least the four lines shown on the screen.
                       Remember to sketch each line on your worksheet according to the directions given.

       

      When you have sketched each of the graphs according to the directions given on the worksheet, answer the discussion questions on the worksheet.

      STOP AND ASK FOR QUESTIONS HERE

      3.  Have the students answer and discuss the following questions:

      A.  What were some values that you found for the slope of a line?
      B.  Are these lines the same in a general sense? Do they fall left to right if negative, increase left to right if
            positive,  zero if horizontal, and undefined if vertical?

      STOP AND ASK FOR QUESTIONS HERE

Strategy 2

                    1.  Have the students go back to the Sketchpad and see if they can find the relationship between the steepness
                         of the line and the value called the slope. They need to draw one line that is almost vertical, one that is
                         almost flat, and two lines that fit in between the two given conditions. Similar to the first time we used
                         Geometer’s Sketchpad sketch the graphs according to the directions given and answer the discussion
                         questions on the worksheet (SHOW THEM A LINE CLOSE TO VERTICAL). Give them five minutes at
                         the most to develop a working definition.

      STOP AND ASK FOR QUESTIONS HERE

      Once the time has elapsed ask the students if they found any correlation between the values of the slope and what the line looks at. They should realize that the slope measures the steepness of the line.

      2.  Conclusion/Wrap-up

      A.  (TIME PERMITTING) Draw the four cases on a board and then have students give me type of slope that
            goes with each line and then have a student repeat the definition of slope.
      B.  Ask the students if we have met the goals for today?
      C.  Ask if there are any questions or things that need to be clarified?

      Link to Slope Worksheet
      Link to Slope Presentation