Thursday, April 28, 2011

Hands-On Graphs and Plots

We learned and reviewed different kinds of graphs and plots with this hands-on activity. First, we started with a graphing kit (a bag with the manipulatives and cut outs for the activities). Here is what we did to learn about these graphs and plots:
 Bar Graph
Materials: different colored and lengths of math rods and graph paper.
What we did:The girls created a bar graph by drawing a horizontal line across the bottom portion of their graph paper, and a vertical line along the left side of the graph paper. They had to leave enough room to write the data information. Then they lined up the rods vertically along that line. Then they determined what they wanted their data to be and wrote it on their graph. One daughter taped her  bars on so she could lift the paper.

Broken-Line Graph

Materials: chocolate chips for the points and toothpicks for the lines with large grid graphing paper
What we did: The girls placed their chocolate chips at different points on their graph. Then they connected them with the toothpicks. They could have simply connected them by drawing a line with a pencil. They also chose what their data would be and included it. Then they got to eat the chocolate chips.


Materials: stickers and large-grid graph paper
What we did: The girls were given a sticker sheet with a variety of stickers. They put the same kind of stickers in a row on the graph paper. Because there was a different number of each kind of sticker, the length of each row was different.

Stem and Leaf Plot
Materials: a "stem" and "leaf" cut out of green paper, dice, and markers
What we did: After learning how to make a stem and leaf plot, the girls rolled two dice to get a two-digit number. They wrote the number down, and then did it five more times. Then they wrote all the tens digits on the green stem. Then they glued the leaf to the stem in such a way that they could write the ones on the leaf in the way that you do with a stem and leaf plot on paper.

Box and Whiskers Plot
Materials: rectangle paper, ruler, and markers
What we did: The girls used a ruler to make and label a number line by tens from 0-100. Then we learned where to place dots when making this kind of plot. You are dividing a list of numbers in four parts. You first have to line them up from smallest to largest. Then you make a dot below the number line under the smallest of those numbers and another one below the largest one. Then you have to make another dot exactly under the middle point, which you find by finding the median of the numbers. Then you put a dot below the middle point between the middle dot and the dots on each end. To do that you have to find the median number between the numbers represented by those dots. After the girls did that, then they learned how to make a "whisker" by connecting the two dots on each side, and how to draw a box around the dot in the middle. Then I let them decorate them by adding more whiskers and making a face in the box.
Scatter Plot
Materials: frosting decorator dots and paper
What we did: The girls scattered a few decorator frosting dots on graph paper to represent the scattered dots in a scatter plot. Then we talked about what kind of data might be represented on a scatter plot. Then the girls got to eat the decorator dots.

Circle Graph
Materials: White 4" paper circles, Pie-shaped pieces of different colored paper cut from 4" circles

What we did: The girls chose which colored pieces they wanted to glue onto their white circle so the "pie" was completely covered and showed different colored sections. Then they labeled the sections to represent the kind of data that might be included in a circle graph.

Monday, April 18, 2011

Run, Jump or Dig -- Ordered Pairs On a Graph

To help remember which way ordered pairs go on a graph
We used a race analogy. When you run a race you have to run on the ground -- or the horizontal line. The starting point of the race is the Zero on the horizontal line (X axis). At the beginning of the race they give you a card with two numbers (or ordered pair of numbers). The first number that tells you how far to run from the starting point of zero. If it is a positive number then you run forward that many blocks or steps until you reach that first number. If it is a negative number, you run backward that many blocks or steps. The second number on the cad represents where to claim your prize. If it is a positive number you will jump up to get your prize. Each prize is located at that specific number, so you have to jump up to get the prize at the exact spot or number of the second number on your card. If the second number is negative, the negative symbol is a shovel, and that means you have to dig to get your prize. Again, when you dig you can only have the prize that is at the exact number that is on  your card.  

How to remember which line is the X-axis.
When you find or graph ordered pairs on a graph, you find the first number on the horizontal line (x-axis), just as in the race, you first run to that number on the horizontal line. When you are ready to run the race, they marked the spot you run to with a giant X made of two axes. Those are the X Axes. You will always see them on the ground (horizontal line) when you run a race. Remember that X marks the spot for your prize.

How to remember which line is the Y-axis.
At the beginning of the race, if the first number they give you is Zero (0) then you stay where you are to either jump or dig for your prize. But the prizes on the vertical line are attached to that vertical line (y-axis), and the only prize you get is two axes. Then you ask them, "Why axes?" If you have to dig for your prize on the vertical line they hand you axes to dig with. Again, you ask, "Why axes?" The second number of the ordered pair that you get at the beginning of the race tells you how far away from the Y axis your prize will be, and whether you have to jump or dig to get it. Hopefully that will help you rememer that the vertical line is the Y axis.