Let's Twist

Maxine Edwards and Mary Teal
The Center for Advancement of Teaching





Let's Twist
Lesson Plan
Algebra 1 Level


Objective: The student will be able to plot data on a scatter plot graph and interpret the information found there. The student will observe the change in light intensity over the given time interval.

Engage: Discuss with the students the different amounts of sunlight received on the earth during a 24 hour period. Discuss how you see and the reactions of the eyes depending on the amount of light present. Examples - Movie theaters- Do the lights in the theater get suddenly dark or is there a gradual lessening of the light? Can you see better in a dark room as the length of time spent in the room increases?

Explore: Group Experiment
  1. Have students stand in a large circle . Try to keep all students equal distance from the instructor who is standing in the middle of the circle.
  2. Give each student a piece of black construction paper with white letters pasted to it. Give the paper to the students FACE DOWN, so that the students do not know what the word is. Student should also have writing utensil and the attached data sheet.
  3. The instructor will stand in the center of the circle holding a light source with a dimmer switch attached to it. Initially the light should be set at the lowest level of light.
  4. Turn off classroom lights.
  5. Students should turn their construction paper over to be face up.
  6. The instructor should begin counting ( as evenly as possible to simulate passing seconds), beginning with 0 and ending with 29. With each increase in numeric value, the light intensity should increase. At the number 9, the light should be at its highest intensity. As the instructor continues to count, the light intensity should decrease, reaching its lowest level at 19. The instructor should continue to count, increasing the intensity to its fullest, to the maximum of 29. (Note: Since this experiment deals with light intensity, it is important that the instructor be seated with the light source unblocked for all students)
  7. As the instructor counts, using the data sheet, the students should individually record either Y or N at each number level to determine if they are able to read the written words or letter on their piece of construction paper. Each student should have a list of 30 numbers and answers at the end of the experiment.

Explain: Discuss light intensity.
Upon completion of the experiment, have the students break into groups of 4 to plot their individual data. All graphs should be marked using the x-axis for the time in seconds as given by the instructor, and the intensity of the light as the y-axis.

(Note: So as not to confuse the students, the instructor will note that the data sheets have been premarked with intensity levels . The levels have been marked using letters of the alphabet. These could easily be replaced by actual wattage amounts if known . For this particular experiment the resultant graph was the topic for discussion, therefore the labels for the y-axis needed to be predetermined to ensure the configuration of the graph.)
Each group will be responsible for presenting scatter plot graphs on transparencies to share with the class. Each transparency would represent data for the combined group with the line of best fit drawn in. Each group graph could be overlaid to see any differences and similarities. This would confirm to all students whether they have correctly graphed the data.

Elaborate:Conduct activity using the EA-100 and CFX-9850G
  1. Perform experiment as follows:
    Equipment
    light probe
    EA-100
    CFX-9850G
    flashlight with adjustable beam capabilities (Ex. STREAMLIGHT,JR)
    meter stick
    Data communication cable
    KEYSTROKE 			EXPLANATION
    a.  Press[SHIFT][MODE]		"Set-up"
        b.Press [DATALOG] until "5 Sec" appears	"Next"  Press [DATALOG] several
        times until the sample time you want
        appears (5 Sec)
    c.  Press[TRIGGER]		Chooses the 5 Sec as the time
    d.  Press[DATALOG] until
    "50" appears Press [DATALOG] several times until the number of sample points you want appears (50) e. Press[TRIGGER] Chooses 50 as the number of samples f. Press [DATALOG] until 1 appears "Next" Press [DATALOG] until you see the time consideration you want. In this case, the time will be collected as data. g. Press[TRIGGER] Selects time consideration. h. Press[TRIGGER] Begins sampling. This means to begin decreasing and increasing the amount of light of the flashlight.
  2. Retrieve the data from the EA-100:
    a. Connect EA-100 to CFX-9850G using the data communication link.
    b. Turn on CFX-9850G and choose Run (1) from the menu.
    c. Press SHIFT VARS {PRGM}
    d. Press F6 (>) , then I/O {F4}
    e. Press Recu (F4) {Receive( }
    f. Press OPTN, List {F1}, List {F1} ,1, close Parenthesis { ) }
    g. Press SHIFT EXE { }
    h. Press Recu (F4) {Receive( }
    i. Press OPTN, List {F1}, List {F1} ,2, close Parenthesis { ) }
    j. Press EXE
  3. The data should now be listed in List 1 and List 2.
  4. For the next part of the procedure you will be operating in the STAT menu
    e. After entering the STAT menu, you should find List 1 and List 2. Press GRAPH {F1}
    f. Press SEL {F4}
    g. StatGraph 1 : DrawOn
    h. EXIT
    i. Press SET {F6}
    Graph Type: Scatter
    Xlist : List 1
    Ylist : List 2
    Frequency : 1
    Mark Type :
    Graph Color: CHOICE
    f. EXIT
    g. GRPH 1 {F1}
    Evaluate: Students will write and explain the intensity of the light with respect to the time the light is recorded. Also the students will be able to explain the relationship of the x and y axis and why the data is only in the first quadrant. Students will explain the relationship of the intensity of the light and the wattage of the light source. Further experiments could be conducted by changing the wattage of the light source . The students will be given new data and asked to create a new scatterplot graph and draw the line of best fit.



    Developed by:
    Maxine Edwards and Mary Teal
    Butler High School Matthews, NC

    additional help from:
    Neal Farley
    Independence High School
    Charlotte, NC