How to Make a Graph on Soda and Tooth Decay for a Science Experiment

Soda might tickle your tongue, but it's horrible for your teeth.

While it is common knowledge that too much soda leads to tooth decay, the extent of the damage it causes is not. A scientific study examining the rate at which soda consumption causes tooth decay over time could prove useful in educating consumers and especially children about the real damage they do to their teeth with each bottle of soda they drink. Since a long report can go over people's heads and feel tedious and boring, the most effective way to present your findings may be to prepare a graph, such as a scatter plot. One glance at a graph like that can teach more about the dental dangers of soda than tens of pages of raw data.

Things You'll Need

• Graph paper

Instructions

1. Draw a large right angle on the graph paper. The vertical part of the angle will be the y-axis and the horizontal part the x-axis.

2. Examine the data for amount of soda consumed and label the x-axis accordingly. For example, say you are measuring soda in terms of average ounces consumed per week, and your data ranges from people who drink no soda to people who drink 100 ounces a week. Draw 10 evenly spaced marks along the x-axis every half-inch or so, and label the first line "10 ounces" the second mark "20 ounces" and each mark accordingly through 100 ounces. Under the axis, label it "Ounces of Soda Consumed on Average Per Week."

3. Examine the data for the rate of tooth decay and label the y-axis accordingly. For example, suppose you're measuring tooth decay by the number of cavities a person suffers in 10 years, and your data ranges from 0 to 15. Mark either 15 evenly spaced tick marks going up the y-axis with each tick mark representing one cavity, or condense the graph and make eight tick marks with each representing two cavities. To the side of the axis, label it "Number of Cavities in 10 Years."

4. Plot the points of correspondence. If someone who drinks an average of 10 ounces of soda per week averaged two cavities every 10 years, find 10 on the x-axis. Move up in a straight line from that spot until you reach 2 on the y-axis, and put a dot in the spot where 10 and 2 intersect. Label this spot as "Person A" or use his name, if you have permission. Repeat this using the data of everyone in your study.

5. Write a title above the graph so people know at a glance what this data represents. In this case it might be "Tooth Decay In Relation to Soda Drinking."

Tips & Warnings

• No matter the precise contours of your experiment, the amount of soda consumed will always go on the x-axis since it is the independent variable, as opposed to rate of tooth decay, which is the dependent variable, which always goes on the y-axis. You can determine which variable is which by asking yourself which variable depends on the other. For example, ask if the amount of soda people drink depends on their rate of tooth decay, or vice-versa.

• Get information about how well soda drinkers care for their teeth, as this will have a significant impact on your data.

References

• University of Illinois; Office for Mathematics, Science, and Technology Education; Scatter Plots
• American Dental Association: Tooth Decay