feature
Engineering design principles help students improve a local park while learning about the forces in structures.
Science and Children—March/April 2021 (Volume 58, Issue 4)
By Christopher Burke and Amy Lazarowicz
Culturally sustaining pedagogy seeks to sustain the lifeways of communities by working to perpetuate and foster cultural pluralism as part of schooling for positive social transformation and revitalization. Creating a culturally responsive (Ladson-Billings 1995) or culturally sustaining (Paris 2012) learning environment requires teachers making connections to students’ experiences outside of school, allowing them to draw on what González, Moll, and Amanti (2006) refer to as students’ funds of knowledge, or the values, interests, and discourse patterns they bring from home, as part of the learning process. This asset-based approach centers understanding and valuing students’ contributions in the classroom. In this article, we describe a five-lesson engineering unit with fourth-grade students to build a picnic table for a local park. The majority of the students at the school speak Spanish as their first language, 14 percent are African American, and 10 percent are White. While 95 percent of the students are eligible for free and reduced lunch, the school’s neighborhood is frequently identified as one of the revitalized and growing communities in the city. The project reflected students’ questions and interests, allowing them an opportunity to directly shape the spaces where they play in the community.
Engineering design lessons are a well-established practice for elementary classrooms. In this class, the process reflected a culturally responsive approach by connecting students’ engaged and extended learning to the students’ community. Connecting science to the community is a critical part of making science authentic for students, thus making it culturally sustaining (Emdin 2016) and cultivating students’ critical science agency (Basu and Barton 2010). There were four practices that resulted in the unit being culturally sustaining:
Asking students at the beginning of every science lesson, “What does a sustainable neighborhood look like?” validated their lived experiences within the community and fostered connections between their experiences and class activities. We also listened carefully to students’ answers and incorporate their responses in subsequent lessons. During these discussions, students would share their perceptions of a sustainable community, noting that they liked the large trees in the neighborhood, the school’s outdoor classroom, and the gardens that some of the neighbors maintained; they also shared a desire to grow more plants. Students were upset by some of the negative aspects of the neighborhood like the noise and pollution caused by heavy truck traffic. They also talked about their role in keeping the neighborhood clean by picking up the litter and trash in the neighborhood. One student stated, “We need to make sure that there are recycling bins in the park so people can throw out their trash.” He believed that unless there were trash cans, the park would become dirty and an unsafe place to play.
The picnic table project started a year before during a lesson on native plants, culminating with planting a pollinator garden in front of the school. Near the end of that lesson a student asked: “Can we build our garden across the street?” The city had recently demolished two vacant houses at the request of the parent organization. The student observed that the empty lots had more space and sunlight to help the plants grow. The teacher responded, “Why not?” which lead to a yearlong effort working with community groups to turn the lots into a park. Building the park ultimately took multiple years and groups of students and involved community activists, neighbors, and nonprofit organizations. While building the park was a community project, it provided a context for multiple community-focused science lessons. We used an interdisciplinary approach to involve different classes in the process of building a park that was co-designed and co-constructed as a space where they were able to play and visit with their families. This ongoing discussion about the connection between the school and the community provided a context in which students’ academic work was given authenticity. In this context, we designed and built picnic tables.
The picnic table unit took five one-hour class periods, using an engineering design cycle to design and build the picnic table where students identified a problem and brainstormed solutions (class 1); designed and prototyped a solution (class 2 and 3); shared their designs (class 4), and built the final product (class 5).
Students were asked to do a quick write in their science notebooks and share what they wanted to do at the park and with whom they wanted to share it. Science journals were a regular part of the science classroom and were used to have students take structured notes, do quick writes, and write reflections on class activities (Baxter, Bass, and Glaser 2001). According to the students, a picnic table was identified as a critical feature of the park that would provide a place for parents to sit and watch them and their younger siblings while they played soccer. The teacher and I decided that the project was well aligned with the standards on engineering design (3-5-ETS1) and a review of the third-grade standards on motion and stability (3-PS2).
The process of identifying the picnic table was a critical aspect of making the project culturally relevant and built upon an asset-based valuing of what these students cared about. The picnic tables reflected the students’ interest in the space, not just as a space for play but a space for extended families to gather. The science content was contextualized and given meaning by their interest in creating a space that they could identify as their own.
The table design process started with students looking through magazines for pictures while working and talking with elbow partners about what the picnic tables could look like. During this process, we did not specifically mention “picnic” tables, and there was an effort to include examples of different styles of benches in the pictures shared with the students to encourage them to think creatively. While we did not allow time in the unit, we recognize that this point in the lesson provides an opportunity to encourage students to do research and learn more about how different communities and cultures structure public dining spaces. During a whole-class discussion, students shared their ideas and pictures drawn in their science notebooks. The students’ discussion focused on functionality, which can be seen in the criteria that they identified to help select a final design. The picnic tables needed to (1) provide seating for up to six people, and (2) be safe and not break.
Several of the students shared their concern that the tables would break or fall over when their family sat on the benches. “I want my abuelo to come to the park with me and I don’t want it to break and make her fall.” To test for safety, the prototype tables would need to support 1kg of weight without breaking or bending. The one kilogram weight, found by the students in the classroom, was chosen as a reasonable substitute for a person to test the scale models.
To prototype the benches, students worked in small groups with preservice teachers from the local university, using craft sticks and hot glue guns to build model benches. The hot glue guns were set up in designated stations; we reviewed safety precautions for using hot glue guns before we started building prototypes. Students only used hot glue guns with the support of a community partner. We selected craft sticks that were 5.5” × 0.3” × 0.1”, which scale roughly to an 8-foot 2×6. In introducing the prototyping process, we discussed scale models and noted that the craft sticks were approximately 1/20 the size of a 2 × 6. Ratios are not grade-level appropriate math content, but we did think that the students could understand the idea of scale models and could understand the idea of the picnic table being 20 times larger than the model. After testing each prototype’s ability to support a 1 kg weight, the students wrote explanations for why their tables worked or failed in their science journals.
For early designs, we focused on points of failure, which informed the students’ efforts to redesign their prototype. The students’ explanations were reviewed to see if they could identify how the force of the weight pushing down on the bench would be transferred through the bench and if they could properly identify that the forces would be unbalanced at the point of failure. In this step, students were engaged in hands-on, analytical testing and problem-solving processes.
After two sessions of prototyping, students shared their designs. They noted that some of the picnic tables fell over when the weight was placed on them, causing them to worry about the tables falling over when their family sat on them. The discussion also created space to share their ideas about what “looked good.” The discussion lead to two new criteria: (1) the table needed to look good, and (2) the table needed to be stable.
Using the four design criteria, students rated all of the prototypes. This process of choosing the final design allowed students to integrate both the more objective data about strength, size, and stability with their own subjective interpretations in determining which table “looked better” and would be a “better table” for their family. For example, Ellon shared, “I really like Corwin’s table with the angles on the top. It looks cool, but it kept breaking when we tested it. It’s not safe.” Corwin had edge glued craft sticks together in a diagonal pattern to form the table top. While there was interest in less traditional designs like Corwin’s, these designs proved harder to build and were rejected by students because the data said that they were not as safe. The final design was selected because it was consistently the strongest and most stable. Miguel stated about the design that the class ultimately selected: “Ana’s design is the best, because the seats are connected and they don’t fall over. It’s also strong, we couldn’t break it with the weight.”
Student prototypes were an instrumental part of the process.
Safety note: Do not allow students to use hand and power tools without appropriate personal protective equipment; e.g., eye protection, gloves, etc. and under direct adult supervision
Using the measurements from the model table selected by the students, we precut all of the 2 × 6s and brought them to class and constructed the table with screws. The lumber and screws were purchased with an internal grant through the cooperating university. Each bench used 11 2×6s and cost $75. After discussing safety procedures for using the cordless drills, each student was allowed to use the cordless drills with the support of a community partner. This opportunity to build an actual table was important in making the process authentic while making the connection between the classroom activities and the community explicit and concrete.
Building the tables also allowed the students to share stories about their parents, some of whom worked in construction trades. Some students asked to bring their parents’ tools to help on the build day and parents volunteered to help build the tables. The project also created opportunities for kids who had worked with tools in the past to demonstrate their expertise.
The picnic table design process was an authentic application of the engineering design process identified in the NGSS (3-5-ETS1). Students defined a design problem and collaboratively generated and compared multiple solutions. They tested these solutions across multiple variables and selected the best one using their measurements of these variables and their own subjective assessments of the final designs. Through the two days of prototyping, students tried multiple solutions to the design challenge and optimized their designs based on established criteria that they measured.
The lesson also addressed the standard motion and stability (3-PS2) by examining the forces that were applied to the table and strategies to ensure they remained balanced, making the table stable and strong. During the design process, we would stop for whole-class discussions about the process.
Teacher: You notice that the table legs would break and the table would fall over when the legs were only attached at the end with glue? How can we make the legs stronger?
Student 1: We need to add more glue?
Student 2: No, more glue still breaks, it breaks where there is glue. We made a triangle.
Teacher: Can you show us what you mean by making a triangle?
Student 2: We added a stick so that it was a triangle with the leg, then it doesn’t break.
During discussions, we defined terms like tension and compression. Students learned that the forces in a structure created stresses, and when a stress was too great, the material would break. Students watched their picnic tables being tested and noted when the stress was becoming too great, because the craft stick would bend and then snap. “When it is just one stick, the leg breaks with the weight. That is too much stress.” After testing their picnic benches, students were asked to identify the points of failure and record in their science journal where tension or compression forces were occurring in the picnic bench and how they might redesign the picnic bench to balance those forces to make the structure more stable. Given our time constraints working with community partners, we did not formally assess the students’ learning, but the students’ notebooks provided access to students’ thinking and learning to determine whether students were applying concepts about balanced forces accurately.
We also highlighted the importance and value of triangles as a way to strengthen structures, noting that triangles are the only shape that cannot change size without changing the length of a side. Students became experts in identifying triangles in different groups' designs. As students shared their designs with the class, it was common for them to complement each other on the incorporation of triangles into the design. In discussions about refining the design, students noted how forces were unbalanced when the stress became too great on one stick. They discussed how to add a triangle to help stabilize the weak stick. Triangles became important because they made the picnic tables stronger and because they made them look better: “Ana’s table has triangles underneath to hold the legs. This makes it stronger and I like the triangles. Callie’s table doesn’t have triangles and it falls over.”
The time constraints for this unit did not allow us to fully address the links to math and ELA Common Core standards. However, we want to note that the project provides opportunities for students to work with solving problems involving measurements (MATH.4.MD.A.1) of both distance and mass. Students also have the opportunity to work at representing and interpreting data (MATH.4.MD.B.4) in tables and graphs. There is also the opportunity to meet ELA standards by having students write a persuasive essay (ELA-LITERACY.W.4.1) supporting their choice for the picnic bench design using the data that they collected.
Efforts to make science and education culturally responsive often reflect stereotypes and narrow definitions of students’ culture. It is easy to construct the experiences of students of color as monolithic representing just one aspect of a community’s culture. By creating multiple and routine spaces for students to define the focus throughout the project, we co-constructed a unit that reflected students’ perspectives about what is important in the community. Their focus on making sure that there were spaces for their younger siblings and parents reflected the importance of family in their community. This project did not begin with our inscribing notions of culture with these students through the curriculum or predetermined project outcomes. Instead, the learning process we nurtured provided the space for students to identify what mattered to them and to drive the inquiry and learning process. In this way, we co-constructed a culturally relevant, community relevant project.
The process of allowing students to develop their own criteria for evaluating the table designs was an important aspect of making the curriculum culturally relevant. The evaluation criteria represented both issues of form and function. The functional evaluations invited students to use their science process skills, making measurements, recording and sharing data in tables and graphs. They also evaluated their designs based on subjective aesthetic considerations. In these cases, students assessed the table as “looking cool” and being comfortable. Students made reference to how the triangles made the design strong and attractive; triangles became a common intersection of form and function in their design.
These design considerations, a blending of form and function, reflect social and cultural values as much as scientific principles. The connections made between the scientific principles and aesthetic considerations were made by students and reflected their social and cultural background and values negotiated in the community of the classroom. The project reflected students’ living culture by drawing on the cultural experiences from home and the community of their peers in the classroom.
Following the unit, we took a small group of students to present about their work at a Place Based Education Community Forum. One of the girls from the class was asked about what she liked most about the project. She responded: “Well my friend here might have a baby someday, and she could bring that baby back to the park and sit on this picnic table. She could tell her baby that she built this park for her.” We, as teachers, make lessons culturally sustaining by listening carefully to students’ questions, intentionally connecting the lessons to the community, giving students a voice in shaping the lesson, and helping students transform themselves and their community through this lesson. ●
Christopher Burke (cjfburke@umich.edu) is an associate professor of science education at the University of Michigan–Dearborn. Amy Lazarowicz (amy.lazarowicz@detroitk12.org) is an elementary school teacher at Neinas Dual Language Academy in Detroit, Michigan.
Engineering Inclusion Instructional Materials Interdisciplinary Three-Dimensional Learning Elementary