Purpose: Students will explore how structure connects in function in everyday objects and in nature. In an extension, students can apply their understanding of patterns in nature and the engineering design process to propose solutions to real-world design challenges.
Procedural overview: Students will choose an everyday object and analyze how its structure relates to its function. Then, students will read the Science News article “Sea urchin skeletons’ splendid patterns may strengthen their structure” and answer questions that connect the article to their everyday object analysis. In an extension, students can apply lessons learned to solve a real-world design challenge.
Approximate class time: 45-60 minutes, plus options for an ongoing in-class or independent project
Everyday household or classroom objects
Computers and access to the internet
Drawing paper and pencils
Directions for teachers:
Part 1: Find a form
Ask students to pick an item from around the classroom or their house. They will analyze how the object’s structure supports its function. Depending on the class, you may want to provide specific examples of familiar objects that students can analyze. Possible objects include: a chair, a milk carton, a running sneaker (versus a sandal), a mechanical pencil or a pen, a spray bottle, a straw.
Ask students to answer the following questions as they analyze their object’s structure and function:
1. Describe the primary function, or the intended activity or purpose, of the object you selected.
2. Describe any secondary functions or requirements.
3. Describe the object’s shape, or the geometric figures you see within it. Describe the structure of the object, or how the individual parts of shapes are arranged and connected. Are there patterns, or repeated shapes or designs, that you notice that may have been intentional in the object’s design?
4. How do the overall shape and structure support the function? Could different shapes and patterns be used to support the same function?
5. What materials is the object made of and how do those materials affect the object’s ability to perform its function?
6. Are there any improvements or alterations you would make to the structure that could better support the function?
After students have answered the questions, instruct them to produce a “schematic” of the object that shows the specific aspects of the structure that support the function. This can be a printed image or drawn by hand and should be done on a separate piece of paper.
Part 2: Lessons from urchins
After completing the hands-on portion of the activity above, have students read the article “Sea urchin skeletons’ splendid patterns may strengthen their structure.” After students answer the following questions in pairs or groups, lead a whole class discussion. Possible student answers are given for each prompt below. Actual student answers will vary. A version of the article appears in the September 10, 2022 print issue of Science News with the headline “The geometry of sea urchin skeletons.”
Possible instructional strategies to use include: partner (think-pair-share) work, small group independent work, teacher-led whole group, gallery walk with feedback (ideas on poster paper and students review each other’s answers).
1. This article discusses the Voronoi pattern. What is the pattern and how does it affect the structure of the sea urchin skeleton?
The pattern is a mathematically based pattern that divides a region into polygons, each built around a point called a seed. Every spot in a polygon is nearer to its polygon’s seed than to the seed of any other polygon. This provides a rigid and strong structure that can withstand predator attacks or other external pressures.
2. Why is this pattern important to the function of the skeleton?
The skeleton protects the sea urchin, which can’t run away from predators. It needs a way to defend its soft tissue. In addition to making the skeleton strong, the pattern makes it lightweight, allowing the organism to survive in underwater environments.
3. Can you think of other examples of patterns in nature that have a functional benefit?
Patterns that give strength are most likely to be found in structures that provide protection or offer an organism stability. There are also visual patterns in nature, such as the patterning and color on flowers or bird wings, that attract other animals, and patterns can also serve as camouflage.
4. How does understanding the structure of the sea urchin skeleton inform your understanding of the design of the object you selected in Part 1?
After thinking about the structure of the sea urchin skeleton, I’m considering how important it is that my object in Part 1 be strong. And how important it is that it is lightweight. I’m curious about the microscopic structure of the materials used to make my object. Do they have a geometric pattern?
5. How could studying the structure of urchin skeletons or other natural objects inform researchers looking for solutions to real-world problems?
The sea urchin might inspire scientists to find new materials that are both lightweight and strong. If scientists can find a way to replicate the urchin skeletal structure with human-made materials, they might be able to design new building materials that can better withstand earthquakes or other natural disasters.
Extension: In sea or space
Consider doing this extension in two parts: The instruction and introduction can be done in class. The student design project can be ongoing in class or assigned as an independent project. Students can work in partners or groups to present their completed designs to the class. This is also a good opportunity to use a consultancy style protocol to show students the importance of communication and teamwork in scientific/engineering endeavors.
Direct students to reread the last two paragraphs of the article “Sea urchin skeletons’ splendid patterns may strengthen their structure.” A version of the article, “The geometry of sea urchin skeletons,” appears in the September 10, 2022 issue of Science News. Have students pay close attention to how the lightweight, strong Voronoi pattern could lead to developments “in materials science, aerospace, architecture and construction.” Ask students to answer the following questions:
1. How does the Voronoi pattern benefit the organisms in which it is found?
2. What other structures in nature show the Voronoi pattern?
Lead a discussion that allows students to brainstorm ideas of where the Voronoi pattern could be used in the area(s) mentioned in the article: materials science, aerospace, architecture and construction.
Show students the following engineering design, development and testing process graphic or use one that is similar.
Talk students through each of the early steps of this design process (ASK, RESEARCH, IMAGINE) using one or both of the real-world situations below. Then have students apply their own thinking to the situation. Students may need access to the internet to explore the constraints and needs of a particular situation, as well as explore past problems and successes. Depending on the class, you may choose to go through the entire exercise as a group or provide a hint that gets students started and then send them off on their own.
Example situation 1: Design a remote vehicle for deep ocean exploration.
Example situation 2: Design a remote vehicle to travel to Jupiter.
For the ASK, RESEARCH, and IMAGINE steps, use the scenario to explain what is done at each step. As students work through each step, they can use the graphic provided to organize their thoughts.
For ASK, tell students that this is typically the first step in the design process. Tell students that “constraints” are used to determine the limitations of the situation. For example, for deep sea exploration, the deeper you go, the more pressure increases due to the weight of the water. The “needs” are the necessary considerations for a successful design. For example, what kind of size and maneuverability would a deep-sea exploration vessel need?
The RESEARCH step is where information is gathered about previous designs that were successful or unsuccessful. You can direct students to brief histories of deep-sea exploration or provide them with examples of successful and unsuccessful deep-sea exploration efforts. The IMAGINE step is the presentation of a possible design or solution. As they come up with a solution, guide students in a discussion that connects back to the relationship between structure and function.