Directions for teachers:
Search the Science News archive to find an article on a topic of your choice that includes a diagram. Some of the answers provided below relate to the Science News article “Rover peers beneath moon’s farside.” Ask your students to read the article, review the diagram and then answer the individual questions below.

Individual questions
1. Describe the diagram included in the article. Explain the different types of information that it contains.

The “Lunar layers” diagram shows a cross-section of the moon’s farside down to a depth of about 40 meters. The cross-sectional diagram includes the different types of soil and rocks within a layer and the approximate depth range of each layer. The Yutu-2 rover is also shown on the surface of the moon in the diagram.

2. What is this diagram’s purpose? Why do you think the diagram is included in the article?

The diagram is summarizing recent data collected by China’s Chang’e-4 lander and Yutu-2 rover. It gives the reader a more efficient way of understanding the data and information that is described in the article’s text by representing it visually.  

3. Give an example of another diagram you have seen or used. Explain its intended purpose.

Answers will vary and could include scientific or other types of diagrams. Students should clearly state what their diagram explains — whether it’s an idea, a process or a system.

Partner questions
With a partner, students should then brainstorm how to define and draw scientific diagrams using the partner prompts below.

4. How would you define a diagram? What is a diagram generally used for?

A diagram is a graphic or image that is created to visually explain an idea, process or system. Diagrams can also be used to organize ideas into categories or define relationships among items.  

5. Think about various fields of science — chemistry, biology, environmental science, physics, genetics and so on. What are some examples of scientific diagrams from these fields?

Phylogenetic trees explain how related organisms evolved from common ancestors. Force or free-body diagrams show all the external forces acting on an object and explain the net force on the object. Biochemical cycles of matter, such as carbon, water, oxygen and nitrogen, are used to explain the interconnectedness of Earth’s resources and how disturbances can affect an ecosystem. A diagram showing an experimental laboratory setup is often used to explain steps of a procedure. Punnett squares are used to predict possible genotypes from breeding experiments and capture their probability. Molecular diagrams explain how the atoms within a molecule are bonded together and can reveal the molecule’s three-dimensional structure.

6. What general steps would you take to conceptualize and draw a diagram? Explain.

To draw a diagram, first define its intended purpose. Determine a level of detail based on that purpose. Outline all of the necessary components and define the relationships among them. Determine how to show the relationships among the components to achieve the diagram’s overall purpose. Add symbols, text and units of measurement as needed. Finally, give your diagram a title.  

Bonus question
Diagrams and models are related tools that are both used to help explain STEM-related concepts but don’t always cover the same breath or depth. Review the questions about scientific modeling from the discussion “Go beyond Mendeleev’s model” with students before asking them to answer the question below as a class.

7. What do scientific model and diagrams have in common? How can they be different?

Scientific models and diagrams are both tools that can be used to organize information, often the components of a system, and to help predict and explain a system’s behaviors and outcomes. Scientific models are generally simplified, ideal representations of phenomena or big concepts. Models are often corrected over time as new information becomes available. Scientific diagrams are generally used to represent a smaller, well-defined idea, process or system. Scientific models can by represented with diagrams, but diagrams aren’t always scientific models. Diagrams require the use of a visual and models can be shown as a visual or explained as a list of components and assumptions. Models can also be physical or mathematical.

Check out the following activities to practice diagramming:
Protective headgear design challenge
Seeing in infrared
Designing soundscapes
Web of changes
Move into a hermit crab’s shell
Journey to the center of the Earth
How do neurons form connections
Reduction-oxidation reaction demonstration