Lessons / Activities : Lessons EA-100

Let It Snow!

Maxine Edwards and Mary Teal
The Center for Advancement of Teaching
Lesson Plan
Algebra 1 Level

Objective: To find the value of the slope of the line given two points. Student will observe the differences in lines with different slope values.

Engage: Demonstrate Dynamic Graphing using the CFX-9850G+ overhead. (Refer to 13-3 of the CFX-9850G+ manual for clarification.)

Explore: Complete the following activity using the EA-100 and CFX-9850G+:

Equipment
motion detector
EA-100
CFX-9850G+
data communication cable
tape
meter stick

  1. Perform experiment as follows:
    Secure the motion detector so that it is flat on a table top and perpendicular to the table top. The cone of detection should be aimed at the walker.
    Connect the motion detector to the EA-100 using the SONIC port.
    Mark a distance of 50 cm on the floor in front of the motion detector. This is the starting point for the walker.
    Let one student practice walking AWAY FROM the motion detector in a straight line and at a STEADY PACE. (Note: The faster the student walks will change the incline of the line graphed.)
    When the student has practiced enough to feel comfortable with walking, begin set up of EA-100.
    To operate the EA-100 manually, use the following keystrokes:
    Keystroke Explanation
    1. Press[SHIFT][MODE]
    		 "Set-up"
    1. Press [DATALOG] until "5 Sec" appears "Next"  
    		Press [DATALOG] several times until the sample time you want appears (5 Sec)
    1. Press[TRIGGER]
    		 Chooses the 5 Sec as the time
    1. Press[DATALOG] until "50" appears
    		Press [DATALOG] several times until    the number of sample points you want appears (50)
    1. Press[TRIGGER]
    		 Chooses 50 as the number of samples
    1. 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
    1. Press[TRIGGER]
    		 Selects time consideration
    1. Press[TRIGGER]
    		 Begins sampling.  This means that it is time to begin the walker.  The student must achieve his steady rate immediately in order to show a constant rate of change
  2. Retrieve the data from the EA-100:
    1. Connect EA-100 to CFX-9850G+ using the data communication link
    2. Turn on CFX-9850G+ and choose Run (1) from the menu
    3. Press SHIFT VARS {PRGM}
    4. Press F6 (>) , then I/O {F4}
    5. Press Recu (F4) {Receive( }
    6. Press OPTN, List {F1}, List {F1} ,1, close Parenthesis { ) }
    7. Press SHIFT EXE {ø }
    8. Press Recu (F4) {Receive( }
    9. Press OPTN, List {F1}, List {F1} ,2, close Parenthesis { ) }
    10. 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.
    1. After entering the STAT menu, you should find List 1 through List 2
    2. Press GRAPH {F1}
    3. Press SEL {F4}
    4. StatGraph 1 : DrawOn
    5. EXIT
    6. Press SET {F6}
      Graph Type: xyline
      Xlist : List 1
      Ylist : List 2
      Frequency : 1
      Mark Type : ?
      Graph Color: CHOICE
    7. EXIT
    8. GRPH 1 {F1}

Explain: Introduce slope formula. Have students take 10 different pairs of data points throughout the graph (or table) and compute the slope for each pair. Discuss what might have caused students' graphs to differ within the graph and amongst each other.

Elaborate:Introduce slope formula. Have students take 10 different pairs of data points throughout the graph (or table) and compute the slope for each pair. Discuss what might have caused students' graphs to differ within the graph and amongst each other.

Evaluate Give students graphs of lines on a coordinate plane. Have students identify two points to find the slope of the line.

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

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