Graphing data is an essential skill in an NGSS aligned classroom. The Next Generation Science Standards require that students use data that they have collected in order to construct their own graphs. Constructing a graph also helps students to analyze and interpret their own data, as well as data that is presented by others.
The Science and Engineering Practice Analyzing and Interpreting Data provides a strong connection between the Next Generation Science Standards and the Common Core standards for math. This practice is an excellent place to look for interdisciplinary connections and design cross-curricular projects.
The ability to create an appropriate graph is also an essential skill that helps students to develop in the Science and Engineering Practices Constructing an Argument Using Evidence and Obtaining, Evaluating and Communicating Evidence. Students can use a graph to support evidence or to communicate their evidence to their peers.
How does graphing in an NGSS classroom align with the common core standards?
Though students do not start discussing variables in relationship to graphs in math until 6th grade, the common core standards do require that students start creating graphs and analyzing data from their graphs early on. The common core math standards require that students draw a bar graph with a single-unit scale starting in second grade. Line plots are introduced in fourth grade. Students will begin to plot points using x and y variables in 6th grade.
What types of graphs should students be making?
While students may know how to construct a graph, they likely will not understand when it is appropriate to use each type of graph. The following are a list of graph types that middle school students should be able to construct:
- Bar Graphs:
- Best for comparing different groups
- Pie Chart
- Best for comparing parts of a whole (especially when broken down into percents)
- Line Graph
- Best for showing change over time
- Scatter Plot
- Good for showing the relationship between variables and graphing large data sets
Selecting the proper graph type helps students to properly convey their evidence and support their argument.
Parts of a Graph
While I have found that most students entering my class are able to construct a graph, their graph is often missing one or more components. Students also often fail to make a connection between the variables that are discussed in their math classes (usually x and y variables) and the variables that they see in their science class. Having students generate their own graphs in your classes can help them to make that connection.
Students should include the following parts on each of their graphs:
- Title: Students should be able to choose an appropriate, relevant graph title. The title of the graph may reflect the type of graph and the purpose of the graph. For example, an appropriate title for a line graph might be Change in Plant Height Over Time. For pie charts, students may want to choose a title that includes the word percent to reflect that this graph type is being used to show the percent of the total that each piece of the pie represents.
- Properly Labeled Axis: Each axis should be labeled on a bar graph, line graph and a scatter plot. The axis should have an appropriate title that shows what is being shown on each axis. Students should also understand that each variable has a designated axis. The independent variable should appear on the x-axis and the dependent variable should appear on the y-axis.
- Key: Sometimes, but not always, students will need to create a key. A key is necessary if students are using different colors or shapes to represent different groups. Students will need to create a key that distinguishes between the groups.
When should students practice graphing?
I introduce graphing the first time that we are collecting quantitative data in my classroom. Graphing is also an excellent skill for students to practice on days when you have a sub.
I have created the following resources to help students construct a graph:
All of these resources can be found here in a bundle on my TPT store.
What strategies do you use to create graphs in your classroom?