Part 1

Graphs are used to illustrate what happens during an experiment.

Bar graph - used for comparing data. Pie graph - used to show percentages. Line graph - used to show continuous

change, usually change over time.

A data table has 2 columns (not always).

The first column is the independent variable.

The second column is the dependent variable.

INDEPENDENT

VARIABLE

DEPENDENT

VARIABLE

This is the factor that we can change.

Example: How long the thermometer is in the water, or how far the runner races.

These are the results we get.

Example: The water temperature, or how fast the runner ran.

Controlled parameters are the factors that stay constant during the experiment.

Example: The amount of salt used or the material used.

Variable Parameters are factors that change during the experiment.

Example: The mass or volume of the gummy bear in water.

Data tables help you organize data.

Graphs help you understand and use data.

An axis is a line that forms one side of the graph.

X-axis: the horizontal line that represents the independent variable.

Y-axis: the vertical line that represents the dependent variable.

To find the range of each axis, subtract the smallest value on the data table from the largest value.

Scale: Each axis has its own scale, or how many spaces between numbers.

You plot the data points by putting a dot on the graph for each pair of data on the data table.

Title: The title tells people what the graph describes. Do NOT use the word graph in your title.

Label axes: Also label the x-axis and y-axis. Include the name and unit label if necessary, like “distance (m)” or “time (sec.)”.

ALWAYS USE A RULER! ALWAYS MAKE AS LARGE AS POSSIBLE! 1) Draw the x and y axes. 2) Label the axes. Include units if needed.

1st column of data table = x-axis2nd column of data table = y-axis

3) Decide - line graph or bar graph? 4) Choose a scale and fill in numbers. 5) Plot your data. 6) Write a title for your graph.

Students' Favorite Candy Bars

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Snickers Milky Way 3 Muskateer Twix Kit Kat

Type of Candy Bar

My Maze Times

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Trial #

T Title

L Labels

U Units

D Data