Statistics Measures of Center and Spread Lesson Plan with Slides

1. Statistics
Measures of Center and Spread Lesson Plan
Before session:
*Note Pod: “Gather Data: Say ‘Toy Boat’ fast. How many
times can you say it before making an error? Type your
number of times in the poll pod.”
*Poll pod: How many times did you say “Toy Boat” without an
error?
*White Board
*Webcam for myself and sharing
*Load PowerPoint slides in share pod
*Welcome music in share pod
*Calculator –TI 83 emulator in share pod
*Chat pod and Private to me Q & A pod set up
PLAN
Play music and have poll pod and note pod ready
for students to do tongue twister as they enter.
Greet by name. Allow them to chat together as
we wait for start of lesson.
Hide music.
Ask for a volunteer to use webcam to say tongue
twister. (Help with webcam technology.)
PowerPoint Slide 1 – Topics: Measures of center
and spread
Slide 2: A rapper lives in your neighborhood in an
incredible house. If you want to impress, would
you use the median or mean house area?
(Sketch right-skewed curve.) Take answers in poll
pod. Watch for wrong ideas of direction of
skewing.
Slide 3: Which would you use to get accurate
picture of prices? (Point out median in middle of
previous curve.) Again, watch answers in poll pod
for formative assessment.
Slide 4: Set of numbers. Review symbols for
number of items and mean.
*animation: 12 changes to 2. Which measure of
center is resistant?
Slide 5: Use toy boat data. Measure spread.
Use TI emulator calculator.
Whiteboard: Sketch histogram of our data.

2. Slide 6: Calculate range of our data. Discuss resistance.
Slide 7: Quick review of Standard Deviation by hand and difference from
formula learned in Algebra 2.
Slide 8: Review of symbols for samples and populations.
*Animation: Take a snapshot!
Slide 9: Calculator directions. Calculator emulator: Look at our data with
TI emulator. Check that they can find the correct values, using chat pod.
Slide 10: Thought question. Give mic rights!
Slide 11: TICKET Out! (Also serves as participation problem for those
watching the recording.)
After:
Review poll pod results. Who is not getting “skewed?”
Email responses to any private Q & A pod questions that I couldn’t answer
in lesson.
Take out student names and post recording on bulletin board.
Emergency plan:
Make recording of concept when technology co-operates and post plus
email to students.
Ask for ticket out responses to be sent for participation points.

3. Statistics A
Ms. Hart
Unit 2.1 – 2.4
Measures of Center and
Spread

4. Mean or median?
1. A rapper lives in your
neighborhood. You want to
impress your relatives. Tell them
about the size of houses in your
area. Use Mean or Median?
2.1 Measures of Center

5. 2. You want to buy a house in
the same neighborhood. To get
the most accurate price, should
you research the median or the
mean house prices?

6. 12, 13, 17, 25, 292
Mean?
Median?
Which measure of center is RESISTANT?
N = number of values in the set

7. 2.2 Measures of Spread
Just how far apart is the data?
Is it so far from the mean that the
mean is meaningless?
Let’s look at your data! How many times you
said “toy boat” fast without an error.

8. Measures of Spread
Range = max – min
Is the range resistant to extreme values?

9. It is NOT the same formula you did in
Algebra 2! What’s different?
Is it Resistant to extreme values?
Standard Deviation: Average distance from the
mean.
By Hand:
* Find mean
* Subtract each value minus mean
* Square the differences
* Add these square values together
* Divide by n-1 (NOT n!)
You have found the VARIANCE. Now, take the
square root to find the standard deviation.
You are NOT expected to ever
do standard deviation by hand
in this class!

10. Symbols

11. Calculator! Everything is easy and ACCURATE!
TI 83 or TI84:
1. Enter data into List 1 Stat > 1:Edit [enter]
2. Stat > Calc > 1:1-varStats [enter][enter]
MathPortal in course:
Starting page does mean, median, quartiles
Scroll down and select Standard Deviation in left
margin for Std Dev Page.

12. Since everything based on the
mean gets pulled by extreme
values, why don’t we use the
median instead?

13. The age of 4 kids:
1 3 5 8
What happens if 10 is added to every value?
Mean? Median?
Std Deviation?
Extra Credit! If
you’re watching the
recording – send
in the answer with
all work shown to
get Participation
points.