Using Calculators to Graph Scatter plots   6/25/2008

Subject: Pre Algebra    Karl Mill

Period: 1  (8:00 a.m.-9:45 a.m.)

Approximate Time:

1 hour, 45 minutes

Objective:

TSW use calculators to graph scatter plots and find the equation for the line of best fit (DOK 1)

5a, 5b

Materials:

Overhead projector, transparencies, vis-a-vis pens, dry erase board, dry erase markers, pencils, paper, textbooks, markerboards, transparency of warm up, guide for teacher on how to create a scatter plot and a line in the calculator, worksheets with categories to create data sets.

Set:  After going over the rules and introducing himself as a new teacher for the class, TTW  review the do now with the students, asking them to explain the procedures step by step.  TTW say that now that we have learned how to plot points for a scatter plot and draw a line of best fit by eye, today our objective is to do them in our calculator and find the exact equation for the line of best fit.  The teacher will ask them to raise their hands if they know who played in the NBA finals a couple weeks ago.  Anyone who can answer will be asked to name as many players as they can who started the last game of the finals, where the teacher's favorite team (The Boston Celtics) dominated the other team.  Today, we're going to be using the shot card in order to set up a scatter plot.  TTW ask for a prediction.  The more shots a player a takes, do we expect the number of shots he makes to go up or down?  After establishing that it should be a positive correlation we are looking for, TTW go on to say that by graphing in the calculator we'll be able to see exactly how positive it is.

Prep:  Name, date, objectives, agenda, and warm up on the board when students walk in the class.  Have notes, warm up, and questions ready before class.

Procedures:

Do Now: (10 minutes)

 On the graph paper provided, complete a scatter plot and graph a line of best fit for the following data set:

X

y

1

8

2

6

3

2

3

1

5

1

6

0

Set: (10 minutes)  

Guided Practice (25 minutes):

The teacher will guide the students through graphing a scatter plot from a table presented on a worksheet, reflecting a box score from a basketball game.  After reading over the table, the teacher will go step by step with the students as they follow along on their calculators.

After everyone gets the graph on their calculator, the teacher will ask the students if their prediction was correct.  

TTW ask the studnets to help him create another table for graphing.  TTW ask the students to rate from 1 to 10 how much they like math and from 1 to 10 how much they like english.  TTW place the student's answers in the x and y column respectively.  After getting the ordered pairs and adding some if necessary, the TTW suggest they try it by hand first and draw the line of best fit, so that they can compare it to what they get in the calculator.  

TTW let the students start graphing it in their calculator and the teacher will check again for correct answers.

Worksheet/Independent practice (55 minutes)

After reminding everyone to keep that guide on their desk, TTW pass out a second worksheet and pair off the students and tell them to graph the first  3 scatter plots.  If students finish early they will be asked to write their answers on the board.  After the students finish those 3 answers, TTW go through each problem and ask if the correlation was positive, negative, and how positive or negative.  By discussing what r means in the calculator, the teacher will explain that it means how correlated the two variables and ask the students to write that down in their notes.  The students will then go on to graph the next three problems in their calculator and answer the questions on the worksheet.  This time, they will work individually.  After they finish, TTW review the answers and collect the worksheets.  

More Independent Practice (If Time allows)

The teacher will write data tables on the board and ask the students to graph in their calculators, checking for correct procedure and answers.

Closure: (5 min)

TTW return to the problem at the beginning, where we saw that you could use a scatter plot to demonstrate something that showed a correlation we all knew was true: the more shots you attempt, the more you are going to make.  Instead of having to graph it, we can use our graphing calculators to plot the points, the line of best fit, and come up with an equation that tells us the slope of the line, the y intercept, and the correlation coefficient, which tells us how strong a correlation there is, or how much one variable impacts the other.  Next time, TSW review what we have been doing with scatter plots, learn some definitions, and prepare for the test.

Assessment/Evaluation:

TSW subtraction binomials and monomials (DOK 1)

2h

Informal: The teacher will observe the students’ progress while they fill out the worksheet (M) to determine how well students graph a scatter plot and identify the equation of the line of best fit (C).

Formal: The teacher will collect the classwork (M) to determine how well the students graph scatter plots and can identify the equation of a line of best fit (C) and record the grade in the grade book (D).