This project lends itself well to graphing. Graphing allows scientists
to see relationships between numbers. Graphs are used to show how a
variable changes over time, show trends in data clearly (i.e. they
visibly show how one variable can change as the other increases or
decreases), and enable the viewer to make predictions about the
results of data not yet recorded. A typical graph has an x-axis
(horizontal) and a y-axis (vertical). In Lesson 4, students will
utilize temperature and precipitation data and create
Bar, Line, and Pie graphs.
- Bar Graphs: Bar graphs are used to compare data.
They are good for plotting data and illustrating how something
changes over time (days, months, years, etc.) and are also used to
illustrate to two compare different items. The x-axis (horizontal)
is typically used to identify the time period and the y-axis
(vertical) displays the numbers for the amount of item measured
(temperature, precipitation, etc.).
- Precipitation(°C) over Time (1 year) of 1 city:
- Temperature (°C) over Time of 1 city:
- Comparison Bar Graph - Precipitation (mm) of 2 or
more cities over Time (date): sample
- Line Graphs: Line graphs show gradual changes in data.
Line graphs are also good for summarizing the relationship between
two pieces of information and how they depend on each other.
- Temperature (°C) over Time (date):
- Temperature (°C) over Time (date) of 2 or more
- Combination Chart: Bar and Line Graph: A comparison chart
displays two graphs on the same graph.
- Temperature (°C) and Precipitation (mm) over Time (1 year) of 1 city:
- Circle Graph: A circle graph, or pie chart, is a circle divided into various
parts to identify different percentages of an item as part of a
whole. For example, the bigger the percentage of a part, the bigger
that part occupies of the circle.
- Scatter Plot: Scatter plots demonstrate a trend in the
data and are similar to line graphs in
that they begin by plotting different data points. However, the
difference is that each of the individual points are not connected
together with a line but rather a trend line is added where
approximately the same number of points occur below the line as
- Temperature (ºC) vs. Elevation (m):
Note: It is important to be aware of how graphs and charts can be
altered (skewed), because the user could be easily misled and create
inaccurate conclusions. Altering graphs can occur purposely or
accidentally. Graphs can be altered several ways including the
practice of not using consistent scales on the axes, meaning that the
values between each point along the axis are not consistent. You
should keep this in mind while the students are creating the graphs.
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