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ACTIVITY in Model of the Atom, Subatomic Particles. Last updated September 28, 2023.


In this activity, students will examine a story about a General who wanted to create an army of soldiers with the ability to walk through walls. Students will evaluate the scenario, generate questions, and use their understanding of atomic structure to explain why it is impossible to pass through a solid wall.

Grade Level

High School

NGSS Alignment

This activity will help prepare your students to meet the performance expectations in the following standards:

  • HS-PS1-1: Use the periodic table as a model to predict the relative properties of elements based on the patterns of electrons in the outermost energy level of atoms.
  • Scientific and Engineering Practices:
    • Constructing Explanations and Designing Solutions
    • Obtaining, Evaluating, and Communicating Information


By the end of this activity, students should be able to:

  • Describe the make-up of an atom.
  • Understand how electrical charges in the atom affect attraction and repulsion.
  • Explain why atoms cannot pass through each other despite being mostly empty space.
  • Write a claim-evidence-reasoning statement using data.

Chemistry Topics

This activity supports students’ understanding of:

  • Atomic Structure
  • Model of the Atom
  • Subatomic Particles
  • States of Matter


Teacher Preparation: 20 minutes
Lesson: 60–80 minutes


  • Computers or devices with Internet access.


  • No safety precautions need to be observed for this activity.

Teacher Notes

  • Begin by creating a Padlet for students to submit questions after watching the video and reading the excerpt. Alternatively, create a space in your classroom for students to form a question board, such as a whiteboard or a Post-it note wall.
  • The goal of this activity is for students to be able to explain why atoms cannot pass through each other despite being mostly empty space.
  • Students will begin the activity by reading a brief one-page introduction about General Albert Stubblebine. Encourage them to focus on the parts of the reading related to the atom. Also encourage any excitement/amusement that is expressed from students to increase engagement in the story.
  • Next show a brief 41-second video clip from the movie “The Men who Stare at Goats.” The video shows the General applying his ideas from the reading. The video will make students laugh at his ideas, and hopefully increase their motivation to engage in the activity.
  • After students have read the excerpt and watched the video, they will generate a short list of scientific questions on the student handout.
  • After completion, ask students to post their questions to the Padlet or to the classroom question board.
  • As a class, select one class question that everyone will investigate. While students could investigate their own questions, choosing one question from all the submissions ensures that students are focusing on a question that fits the objectives for the lesson and requires scientific investigation.
  • In an effort to select one strong question as a class, the teacher can identify commonly asked questions and/or strong scientific questions. Share the questions with the class and encourage discussion. The teacher can help by asking additional questions such as:
    • Do we need to complete scientific investigations to answer this question?
    • Will we learn something we did not know before about atoms by investigating this?
    • Can we write a claim, evidence, and reasoning to answer this question?
  • Example potential questions that would be good choices:
    • Why can a person walk through a wall of water, but not a wall of brick?
    • Why do we not travel through the empty space in atoms?
  • When the class question is determined, students will record it in the appropriate space on their handout. Next, they are asked to predict an answer to the question and provide an explanation.
  • It’s helpful to have a small discussion at this point to think about the specific information that needs to be collected. This helps to guide students to think about what information is important (and helps avoid the use of Google). A teacher can help direct the discussion by asking students questions such as:
    • What is inside of an atom?
    • Where is the empty space in an atom?
    • Can I pass through a wall due to the empty space in an atom

  • Next, students are given 30-45 to investigate four resources. This helps guide their exploration (rather than relying on Google to answer the question). Encourage students to use all four resources to make complete observations. Students should organize their observations in data tables (see answer key for examples):

  • If students finish early, encourage them to begin working on the claim, evidence, reasoning section or help other groups complete their research.
  • If a student gets stuck during the investigation section, it can be helpful to use guiding questions to direct them. Sample questions are provided below:
    • What happens if you bring two atoms really close together? Do they attract or repel each other? (see Atomic Interactions PHET simulation)
    • What do the atoms in a solid look like? How could this relate to General Stubblebine not being able to pass through the wall? (see States of Matter PHET simulation)
  • It can be beneficial at this point to ask students to share one fact about the atom that they learned from their research with another student.
  • Finally, students write a “claim, evidence, and reasoning” response for the class question. Often students will add their opinion in the evidence section instead of relying on observations. Additionally some students might have difficulty using proper reasoning, and instead just restate their clam in this section. Teachers should be mindful of redirecting students in these instances. Examples of correct “claim, evidence, and reasoning” responses are provided in the answer key.
  • As a class, discuss what was learned in the activity and generate a list of “things we know about atoms.” This is a helpful summary for student reference in future lessons.
  • Differentiation can be accomplished in several ways in this activity.
  • Teachers can provide a list of resources for the research component, as well as offer data table examples for reference. The “claim, evidence, and reasoning” response section can be scaffolded to provide additional support. Examples provided below:
    • Claim: General Stubblebine could not pass through the wall due to …
    • Evidence: I observed that atoms … I also observed that atoms … (including multiple data points here helps point students to the idea that often times, more than one piece of evidence is needed.)
    • Reasoning: When we are explaining something using science, there are certain science principles that are true that can be used to show why the evidence supports the claim. In this case, that is the philosophy that like charges repel each other. Example: Because … (give scientific principle), our evidence supports our claim since …
    • For more examples, see CER Frames, created by the science teachers at Sunnyvale School District.

For the Student


Read the passage below about General Albert Stubblebine. As you read, record at least three observations in the space provided. Keep in mind:

  • What information is the most important?
  • What information do you need?
Source: Wikipedia

Reading Passage

Part 1:

Albert "Bert" Newton Stubblebine III (February 6, 1930 – February 6, 2017) was a United States Army major general whose active duty career spanned 32 years. Beginning as an armor officer, he later transferred to intelligence. He is credited with redesigning the U.S. Army intelligence architecture during his time as commanding general of the U.S. Army Intelligence and Security Command from 1981 to 1984, after which he retired from active service.

Over the course of his retirement, it became widely known that Stubblebine maintained a keen interest in psychic warfare throughout his service. He sought to develop an army of soldiers with special powers, such as the ability to walk through walls.

Part 2:

Visit the Library of Congress webpage below and read the sample text from the book, Men who Stare at Goats.



Next, record three scientific questions related to the reading. Focus on what you are curious about! Consider any prior knowledge you may have and use this to ask deeper questions. For example:

  • What assumptions did you make about the situation?
  • Is it scientific?
  • Does it start with how/why?
  • Are you curious about it?
  • Can you generate a scientific experiment to test it?

Scientific Questions

Chosen Class Scientific Question

  1. Based on all the question generated, your class will choose one question to further investigate. Record the question below:
  2. Briefly predict the answer to the question chosen above. Include an explanation.
  3. What can you measure, observe, and/or change in an experiment that is focused on atoms to help answer the question?


Use the following websites to collect observations and data to help answer the class question:

Use the space below to record your observations and data. Be sure to explain what you were observing and how you observed it. Scientists record observations in data tables.


  1. Answer the class question using claim, evidence, and reasoning.


(What causes this?)

(Give data from your observations to back up your claim.)

(How does the data support this? Refer to scientific principles.)
  1. Create a model to support your CER response. Ensure that your model shows why or how it happens.