Critical_Thinking Creative_Problem_Solving Effective_Communicating

CHAPTER 6
Strategies for Teaching the Engineering Process

What Is It?

The engineering process is a series of steps used by engineers to solve a problem. It generally includes designing an apparatus. Although the steps vary depending on the source, the central idea is the same: solutions must be tested multiple times to ensure a high-quality design.

The Next Generation Science Standards (NGSS) require students to use the engineering design, which consists of these three steps that are formatted as a cycle, with no beginning and no end (NGSS, 2013d):

  • Define
  • Develop Solutions
  • Optimize

The definitions of these three steps vary by grade level, but they have the same basic meaning.

  • Define—identify a problem and its criteria.
  • Develop Solutions—use research to create solutions or break down big solutions into smaller solutions.
  • Optimize—test solutions and then ensure they meet all criteria.

The NGSS emphasize that there is no particular order for these steps (NGSS, 2013d). Most often, the steps are not linear because throughout the process engineers learn new information or think of new ideas. This requires them to return to previous steps to incorporate new learning or ideas into their prototype design.

We've found it helpful to break down these three large steps from the NGSS into nine non-linear smaller steps. In our experience, these nine steps are more concrete, which increases student understanding of what is expected of them. The steps provide a detailed description of how students move through the engineering process. Here are the engineering process steps we teach our students:

  1. Ask a question.
  2. Perform research.
  3. Brainstorm solutions.
  4. Choose one solution.
  5. Build a prototype.
  6. Test the prototype.
  7. Reflect on the results and redesign.
  8. Communicate results.
  9. Begin again with step 1.

This chapter focuses on the engineering process, while Chapter 3 provides strategies for teaching the scientific method, Chapter 4 includes resources for the inquiry process, and Chapter 5 focuses on project-based learning.

All four processes can engage students. In our experience, students most often confuse the scientific method and the engineering process. Based on Table 6.1: Differences Between the Scientific Method and the Engineering Process, the scientific method has a structured beginning and ending; however, the engineering process requires scientists to return to previous steps so that they can incorporate their learning into new designs. The scientific method has only one independent variable because the purpose of an experiment is to determine how that variable affects the experiment's outcomes. However, in the engineering process, there can be many independent variables because scientists can test the efficacy of any aspect of a design.

The engineering process usually includes a diagram of a new design that will be tested, which acts as a substitute for the formal hypothesis that is required by the scientific method. The last difference between the scientific method and the inquiry process is that when an experiment is complete, the scientist determines if the experiment should be repeated with or without alterations. However, in the engineering process, the redesigning never ends because all processes and mechanisms can be improved.

Table 6.1 Differences Between the Scientific Method and Engineering Process

Scientific method Engineering process
Is a linear process with a clear beginning and ending Is not linear; does not have a structured beginning and end
Must include only one independent variable May include multiple independent variables throughout the process
Must include a formal hypothesis May include a hypothesis
May include retesting Must include retesting

When we introduce the engineering process to students, we summarize the differences between the scientific method and the engineering process. We explain that when scientists design a new or improved technology, success is almost never accomplished the first time. Engineers create a new design, test it, learn from the testing, apply their learning to another new design, and so on. They don't publish their findings until after they've created a new design that meets the minimum criteria. For this reason, a linear process like the scientific method is disadvantageous.

Why We Like It

When students are using the engineering process, they are also reinforcing the skills they use in the scientific method, inquiry process, and project-based learning. All four of these processes include scientists asking questions, performing research, and communicating their results.

As students work through the engineering process, they are consistently challenged to analyze the effectiveness of their ideas and improve their current designs. Students will often attempt a solution but then realize during or after implementation that their solution isn't as effective as they had originally hypothesized. According to research, making these kinds of mistakes and performing this type of analysis change how a person's brain organizes information (Castro, 2011). Students are certainly learning by using the engineering process, and that is the purpose of science!

Supporting Research

There are benefits to using the scientific method, project-based learning, the inquiry process, and the engineering process in science classrooms. However, the NGSS particularly highlight the engineering process because it clarifies for students, “the relevance of science, technology, engineering, and mathematics (the four STEM fields) to everyday life” (NGSS, 2013g).

The engineering process can also allow for students to use creative thinking, and can help them develop the needed self-confidence to think “outside the box” and solve problems. Becoming skilled in the engineering process promotes critical thinking skills that students can employ as they encounter future problems (Cowan, 2013).

Skills for Intentional Scholars/NGSS Connections

The engineering process incorporates all three Skills for Intentional Scholars. Students use creative problem-solving skills as they brainstorm solutions. They also practice their critical thinking skills as they determine the best possible solution and analyze the effectiveness of their prototype. Finally, students use communication skills to publish their results.

Historically, there's been a division between teaching students science content and science practices. The NGSS attempt to combine the two by requiring the use of engineering practices (National Research Council, 2012, p. 42).

Application

When first presenting the engineering process to students, we introduce Thomas Edison, the inventor of many technological advances, including the phonograph, an incandescent light bulb with a carbon filament, and nickel-iron batteries. We begin by showing students a picture of Thomas Edison and asking them to share with us what they already know about him. After all students have the opportunity to share their knowledge, we tell them the full history of how the light bulb was invented and improved.

Here is the story we tell students:

The original light bulb was invented in Britain as early as 1802 (Matulka & Wood, 2013). The design was expensive to produce and it had a short lifespan. Beginning in the mid-1800s, Edison worked for several years to improve the design. In October, 1879, he and his team created a light bulb with a carbonized cotton filament that lasted for 14.5 hours. And by January of 1880, they improved their design further by using carbonized bamboo filaments, which remained lit for 1,200 hours and could be produced for a much cheaper price (Engineering and Technology History Wiki, 2015).

We pause at this point in the Edison story to write the following nine engineering process steps on the board:

  1. Ask a question.
  2. Perform research.
  3. Brainstorm solutions.
  4. Choose one solution.
  5. Build a prototype.
  6. Test the prototype.
  7. Reflect on the results and redesign.
  8. Communicate results.
  9. Begin again with step 1.

We explain to students that this is the process engineers use to solve problems, such as improving a current technology like a light bulb. Then we continue the tale…

The most interesting part of Edison's story involves his tenacity to find a successful design. When he completed Step 7: Reflect on the Results and Redesign, he often realized his proposed design didn't achieve his goals for a cheaper, more efficient light bulb. He chose not to quit but, instead, to return to Step 2: Perform Research or Step 3: Brainstorm Solutions, at which time he identified additional solutions.

The engineering process helped Edison view his failures as learning opportunities—he never gave up! In the 1910 biography, Edison: His Life and Inventions (Dyer & Martin, 1910), Edison's friend Walter S. Mallory asked him, “Isn't it a shame that with the tremendous amount of work you have done you haven't been able to get any results?” Mallory reflected on the conversation and recalled that Edison responded quickly, “Results! Why, man, I have gotten a lot of results! I know several thousand things that won't work.” (Quote Investigator, n.d.)

After we share the story of Thomas Edison, we ask students to write about an event in their lives when they first failed but chose not to quit. Students share their stories with a partner and then we ask for volunteers to share with the rest of the class. We ask students how they felt when they finally succeeded after trying again and again. Then we ask students how they think Edison must have felt after finally inventing a light bulb that stayed lit for 1,200 hours and was economically feasible. We acknowledge that failing is frustrating; however, we also explain that it's less frustrating when we see mistakes as learning opportunities, like Edison did when his ideas failed. And when people don't quit but instead persevere, they are more likely to meet their goals.

We find this is an excellent opportunity to discuss the concept of a growth mindset with students. We begin by explaining the difference between a fixed mindset (the belief that a person's talents and traits don't change over time) and a growth mindset (the belief that abilities can be developed over time). Then we show the students a quick interview with Carol Dweck, the leading researcher on fixed and growth mindsets. As we do with all videos, we give the students a purpose for watching it by telling them that after the video, they will be responsible for determining which mindset is practiced during the engineering process. The video we show is called “Carol Dweck on the Difference Between a Fixed and Growth Mindset” (2014) and can be found at https://www.youtube.com/watch?v=hXyesVD4EJI. Many others are also available online.

After the video, students have a discussion with a partner about which mindset is practiced during the engineering process. We remind them that the steps of the engineering process are written on the board and encourage them to use the steps as a reference. We walk around, listening to student conversations to ensure students are on task. If students struggle to correctly identify the answer, then we ask them, “Which mindset do you believe Edison had?” This most often leads to students making the growth mindset connection.

As individual groups determine that the answer is a growth mindset, we further challenge their thinking by asking, “Which step of the engineering process provides the most opportunities to practice having a growth mindset and why?” Then we have a classroom discussion by asking for volunteers to share their answers. Students often say, “Step 6 offers the most opportunity because sometimes a prototype won't work as planned.” Other students may disagree, which is okay because there is no right or wrong answer. The purpose of the conversation is to have students make a connection between having a growth mindset and using the engineering process.

Once students are aware of the advantages in having a growth mindset, we again point their attention to the board where the nine steps are written. They are directed to discuss with their peers which steps would be the most frustrating to perform but might provide the most learning. Students' answers may include steps 5–7 because Step 5: Build a Prototype requires the actual designing, Step 6: Test a Prototype requires testing the design, and Step 7: Reflect on the Results and Redesign requires analyzing the results. In all three of these steps, engineers may find flaws in their designs.

We pose the question, “What did Edison do when he realized that his design had shortcomings?” Students respond with ideas such as returning to steps 2 and 3 to perform further research and brainstorm more solutions. We agree and then explain this is how engineers use the engineering process. Engineers don't begin with step 1, complete all subsequent steps in order, and neatly end with step 9. Instead, they weave back and forth between researching/brainstorming and building/testing/reflecting. This is a good time to reinforce why engineers can't use the scientific method—it doesn't allow a scientist to return to a previous step.

After students have developed a basic understanding of the engineering process, we launch a lesson that helps them put it into practice.

STEP 1: ASK A QUESTION

The first step of the engineering process is to ask a question, which we address in Chapter 5: Strategies for Using Project-Based Learning. Chapter 5 includes ideas that help both teachers and students generate questions.

To introduce the engineering process to high school students, we challenge them to make a catapult using mousetraps. The question we ask students is, “How can a mousetrap be used to catapult a marshmallow the farthest distance?”

Using mousetraps can be dangerous so, when we work with elementary and middle school students, we instead have them participate in an egg drop challenge or the Pringle potato chip mail challenge. The egg drop challenge requires students to drop an egg from a high distance without it breaking. The question we ask would be “How can an egg be packaged so that it does not break when dropped from the roof?” The Pringle chip challenge requires students to mail a single chip to their house in an envelope and have it arrive in one piece, without any damage. Pringle potato chips are generally the same size and shape, which can be an experimental constant that is unlikely to be found using other potato chip brands. The question for this engineering challenge would be “How can a Pringle potato chip be packaged so it does not become damaged in the shipping process?” Online resources for the egg drop and the Pringle potato chip challenge are available in the Technology Connections section.

We review the following steps specifically discussing the mousetrap catapult example; however, most of these same steps can be applied to any other engineering challenge, including the egg drop or Pringle potato chip challenge. The only exception might be that it would obviously be time-consuming to do multiple tests of the Pringle potato chip challenge.

STEP 2: PERFORM RESEARCH

Before students can define the problem, they must first understand how catapults work.

We begin by showing them two online videos: one of a working trebuchet and another of a catapult (plenty can be found online). Prior to viewing any video with students, we give them a purpose for watching it. We tell students that the purpose of viewing these videos is to learn how trebuchets and catapults launch projectiles into the air. After both videos have been shown, students discuss their observations with a partner. Then we have a class discussion about how catapults use tension while trebuchets use counterweights. We've found that student understanding increases if we show the videos again after the class discussion because now students have a greater ability to comprehend what they are seeing.

After determining how catapults work, students learn about the mechanics of mousetraps. We pass out a mousetrap to each pair of students (after having a serious conversation about safety) and model how to set, hold, and release a mousetrap. Students then practice so they become more comfortable using them.

In the engineering process, students need to research the following two main concepts:

  1. Define the Problem: Research any one or all of these questions:
    1. What is the problem?
    2. Why is it a problem?
    3. For whom is it a problem?
  2. Identify Current Solutions: Researching any one or both of these questions:
    1. What are the current solutions?
    2. What are the solutions' shortcomings?

In the mousetrap catapult challenge, the question we ask students is, “How can a mousetrap be used to catapult a marshmallow the farthest distance?” In other words, we introduce them to a contest! To provide students with a “starting off point” regarding identifying the problem and its current solutions and shortcomings, we write the following questions on the board or display them on a document camera:

  1. What determines the distance a mousetrap can fling a marshmallow?
  2. How can those factors be maximized?
  3. How can the marshmallow be adhered to the catapult?
  4. What additional resources do other people use to make mousetrap catapults?
  5. Which designs fling the marshmallow the greatest distance?
  6. What are the shortcomings of the solutions other people have used?

We tell students they will need the answers to these six questions in order to design an effective mousetrap catapult. Students work in groups of three or four to complete their research online. See Chapter 3: Strategies for Teaching the Scientific Method and Its Components for materials to help students perform research. They document their findings in a shared Google document, in their science notebooks, or in their notes.

After groups complete their research, we have a class discussion to define one common problem. Each group is instructed to write their defined problem on a dry erase board, which is 2 × 2 ft. These boards can be purchased and cut for a reasonable cost at any home improvement store. If mini-whiteboards aren't an available resource, a sheet of paper can be an effective substitute.

We instruct students to begin their problem statement with the phrase, “We need to…” They are also instructed to include the dependent variable in their problem statement.

One-by-one, groups share their dry erase boards with the rest of the class. We then facilitate a class discussion to write one problem that will be shared by the whole class. The two most common problems identified by our classes are:

  1. We need to use a mousetrap to catapult a marshmallow the farthest distance possible.
  2. We need to launch a marshmallow the farthest distance by using a mousetrap catapult.

We approve the class's problem statement if it includes the main idea of the question and the dependent variable, which in this example is the distance the marshmallow flies.

Then it's time to combine all of the groups' research regarding how other people have attempted to build a mousetrap catapult and the shortcomings of their designs.

We draw a T-chart on the board in the front of the classroom. The first column is titled Current Solution and the second is titled Shortcomings. We ask groups to report on their research and we note it on the board. Groups share any current solutions other people have used and the shortcomings of those solutions. This list is kept on the board for the remainder of the challenge so students can use it as a reference.

For the mousetrap catapult challenge, a common T-chart may look like Table 6.2.

Table 6.2 T-chart for Mousetrap Catapult Challenge

Current solution Shortcomings
Spoon is taped to the mousetrap's metal bar The spoon can easily be taped on the incorrect side of the bar
Spoon is taped to the mousetrap's metal bar The spoon can easily be taped facing the opposite direction the bar swings
Spoon is adhered to the mousetrap's metal bar with a rubber band The rubber bands often break
Mousetrap is taped to the floor Scotch tape and masking tape aren't strong enough
Mousetrap is triggered with a pencil Wooden and mechanical (plastic) pencils break

STEP 3: BRAINSTORM SOLUTIONS

Now it's time for students to use what they've learned from the research process to brainstorm their own design ideas.

Brainstorming sessions require a structured process that facilitates a creative environment. The goal is that students produce as many possible solutions without parameters or real-life restrictions.

Ideation is the process we use to help students brainstorm ideas. We prefer ideation over all other brainstorming processes because it includes both individual and group think time. It's important to provide the individual think time because research touts that brainstorming sessions include more diverse ideas when people have time to brainstorm individually (Torres, 2016).

Further research finds that when brainstorming sessions begin with the whole group “throwing out” ideas at the same time, only the loudest students are heard. However, when individual brainstorming occurs first and is then followed by a round robin group discussion, student confidence and learning can increase, specifically for English language learners (Asari, Ma'Rifah, & Arifani, 2017).

The ideation process includes two steps.

Step 1: Individual Brainstorm Time

To brainstorm in an organized manner, each student is given a set of sticky notes, index cards, or strips of paper. They are instructed to think quietly and write down every idea that comes to mind. This requires approximately 5–10 min. Students can also draw pictures to represent their ideas, which can be especially helpful for newcomer English language learners.

Students are told to write only one idea on each paper because it helps to keep individual ideas organized during Step 2: Round Robin Discussion.

Step 2: Round Robin Discussion

Students are broken into small groups of three to five. See Chapter 2: Strategies for Teaching Lab Procedures for strategies that can be used to create student groups.

There are several methods for productive round robin discussions. Our favorite is to have each group sit in a circle. One student in the group stands up, shares one idea, and sits down. They place their written idea in the middle of the circle. If another student has the same idea, they immediately pile it onto the previous student's idea. By the end of the round robin discussion, there are multiple piles, each representing a different idea.

We've found some individuals are verbose in their explanations, so using a timer can be helpful. We allow only 30 s of share time for each idea.

In our mousetrap example, students brainstorm designs that would make their marshmallow fly the farthest distance. Some students' ideas focus on the amount of tension, others' ideas are framed around stabilizing the mousetrap when it is released, and yet other students will have ideas that center around how the marshmallow is connected to the mousetrap. The goal of brainstorming is that all of these equally important design ideas are shared so they can be incorporated into the final product that will launch the marshmallow the farthest.

Prior to introducing the ideation process to students, we explain the four rules of ideation. According to Nick Bogaert, there are Four Golden Rules for ideation (Bogaert, n.d.), which we place on the board and teach to the class. The four rules are:

  1. There are no bad ideas.
  2. Capture everything.
  3. Go for hybrid brainstorming.
  4. Quantity over quality.
Rule 1: There Are No Bad Ideas

In our experience, this rule is easier for younger students. And conversely, the older the student, the more difficult it can be because they tend to have more social inhibitions and are beginning to see the world through critical eyes. To help older students feel comfortable sharing their ideas, we explain the purpose of this rule.

We explain that the point of the ideation process is not to identify solutions but, instead, to document ideas. No one is allowed to judge anyone's ideas or add restrictions by saying things such as, “yes, but.” This is a time for students to be creative and silly. We further explain that sometimes one silly idea will lead to a viable solution so all ideas are good ideas during an ideation session.

During Step 2: Round Robin Discussion, we walk from group to group and redirect any judgmental comments we hear by saying things like, “Remember that this is a brainstorming session so there are no bad ideas” and “Please don't judge each other's ideas because when we brainstorm there are no bad ideas.”

Rule 2: Capture Everything

This rule pertains to both steps of the ideation process. In Step 1: Individual Brainstorm Time, students should document every idea they have; they should not dismiss any of them. During Step 2: Round Robin Discussion, we provide additional sticky notes, index cards, or strips of paper to each student. They are encouraged to write down any additional ideas that come to mind while their peers are sharing. They then share these new ideas, one at a time, when it is their turn.

The ideas students think of during Step 2: Round Robin Discussion may be the best ideas created. When students first begin brainstorming, research states that more and better ideas are generated when individual ideation occurs first and is followed by a group share (Girotra, Terwiesch, & Ulrich, 2010).

Rule 3: Go for Hybrid Brainstorming

This rule encourages students to combine one peer's idea with another during Step 2: Round Robin Discussion. As students are sharing their individual ideas, thoughts might come to group members about how to combine some of them. During this time, they can write their hybrid ideas on a sticky note, index card, or strip of paper and then share them with the group when it is their turn.

Rule 4: Quantity Over Quality

This rule encapsulates the other three rules. The best ideation sessions create the most ideas. We explain to students that they will generate many ideas by being true to the first three rules. We remind them that the goal of brainstorming is to generate multiple ideas in order to synthesize the best possible solution when the brainstorming session is complete.

STEP 4: CHOOSE ONE SOLUTION

After the brainstorming is complete, it is time for students to make a decision about how to proceed with their design. We introduce this step by discussing “universal design principles.”

When engineers design a product, they generally design for the average user but should be designing for all types of people (Burgstahler, 2015). Engineers and engineering students can be encouraged to analyze their ideas using the following seven universal design principles:

  1. Equitable use—people of all abilities can use the product.
  2. Flexibility in use—people of all interests can use the product.
  3. Simple and intuitive—people don't need background knowledge to use the product.
  4. Perceptible information—people receive easy-to-access information from the product.
  5. Tolerance for error—people are safe from harm when using the product.
  6. Low physical effort—people don't exert themselves or feel fatigued after using the product.
  7. Size and shape for approach and use—people of all shapes and sizes can easily use the product (for example, people who are left-handed).

When we introduce these seven principles, we project them on the board and ask students, “What is the common theme among these seven principles?” After students discuss this with a partner, we facilitate a class discussion. If students are struggling to recognize that each principle revolves around the user, we ask them to identify the common word in all seven principles, which is the word “people.” This usually kick-starts a class discussion about how products have no value if people can't use them.

We encourage students to design with the user in mind. For example, when planning their mousetrap, students should design it so that every student in the class—regardless of physical ability—can properly launch the marshmallow with little, if any, instruction.

Research suggests that when engineers use the seven universal design principles, their end products are more user-friendly, especially for people with disabilities (Bigelow, 2012). This is an opportunity for students to practice social emotional awareness because they are designing for people who may be different from themselves.

While in their lab group, we also suggest that students continue brainstorming ideas, especially if they can combine two seemingly different ideas. For example, if one student had the idea to brace the mousetrap by taping it to the floor with duct tape and another student suggested that the marshmallow be placed in a spoon that is taped to the mousetrap, then the chosen solution could incorporate both ideas.

Sometimes, students can't decide between two different design solutions. To help them determine which is the better of the two, we recommend they build the first design and test it multiple times. Then they build and test the second design multiple times. After calculating the average distance for each design, students then choose the design that slung the marshmallow the farthest distance.

STEP 5: BUILD A PROTOTYPE

Once a group decides which ideas to use, we require them to draw a diagram. We teach students that diagrams are pictures with labels indicating the materials used in the design and how the materials will be adhered to one another. We show students Figure 6.1: Student Examples of Mousetrap Catapult Designs, which offers two student examples of well-drawn diagrams. Figure 6.2: Mousetrap Catapult Lab Worksheet is the worksheet we provide to each student so they can record their designs, data, and design changes.

After their diagram is complete, we remind them that they may find that their idea isn't going to be successful, and that is okay. We tell the class that this is a natural part of the engineering process, offer a reminder about having a growth mindset, and encourage them to focus on the fact that they learned something. They simply need to return to their list of ideas and find another. Once this class discussion is complete, the groups gather all necessary materials and begin to build.

STEP 6: TEST THE PROTOTYPE

Once students have a prototype, they test it to gather data that will determine its effectiveness. In the case of the mousetrap catapult, students launch their marshmallows in the classroom, hallway, and/or outside depending on the space available and weather conditions. Students measure the distance the marshmallows fly. They are instructed to document their data in a data table and complete at least two more trials. See Chapter 3: Strategies for Teaching the Scientific Method and Its Components for resources to teach students how to make and use data tables.

To ensure students are launching their marshmallows in a responsible manner, we review lab behavior expectations. See Chapter 1: Strategies for Teaching Lab Safety for resources to teach students proper lab behavior.

STEP 7: REFLECT ON THE RESULTS AND REDESIGN

After students collect at least three trials' worth of data, they analyze the data to determine if their design can be improved. If they determine a change to the design will improve their results, they redraw their diagram, alter the prototype, and test again. Figure 6.1: Student Examples of Mousetrap Catapult Designs includes two student examples of diagrams.

To encourage students to keep designing, testing, and analyzing, we have them compare their data to other groups' data to determine if their design is the most effective or if they should be receiving better results. Students must redesign and retest several times before they find a design that provides optimum results. When a group insists their design cannot be improved, we give them an additional challenge. As an example, in the mousetrap catapult lab, we challenge students to improve their design for accuracy. Using tape, we mark off an X on the wall or floor and challenge the students to hit the X from a specific location.

STEP 8: COMMUNICATE RESULTS

Students can share their results in writing through a lab report, slideshow, an article on a class blog, and/or in many other forms.

In Chapter 3: Strategies for Teaching the Scientific Method and Its Components, we provide resources for students to document their results. In Chapter 5: Strategies for Using Project-Based Learning we've included resources for publishing student results to an authentic audience.

STEP 9: BEGIN AGAIN WITH STEP 1

True engineers never stop designing. To make this point with students, we show them a picture of an original cell phone, informally called a brick phone. We explain that this phone was wireless but could only make phone calls. Students are challenged to list the improvements that cell phones have undergone throughout the years. Students may list such things as access to the Internet and social media, the invention of apps and games, the addition of a calculator or GPS, and texting.

We use the cell phone example as motivation for students to continue improving their design. We ask guiding questions such as, “Can a person in a wheelchair activate your mousetrap?” and “Can a child safely activate your mousetrap?” The goal is that students begin to think about unique users and their needs.

After all students have made revisions and are confident with their designs, they are allowed to complete three official trials to obtain the farthest distance for the contest. The winning group earns a token of our appreciation (extra credit, food, or other incentives).

See Figure 6.3: Mousetrap Catapult Picture for a picture of a mousetrap catapult that was made in our classroom.

GRADING ENGINEERING PROJECTS

There is no right or wrong answer when students use the engineering process. To assess their learning, we grade them based on the documentation they make during the engineering process. When we first introduce an engineering task, we provide each student with a copy of the rubric so they know how they will be graded. We've included an example of our mousetrap catapult rubric in Figure 6.4: Mousetrap Catapult Rubric. Students are provided time to read the rubric and then we ask them to summarize how their products will be graded. After students identify that it is their documentation that will be graded, we ask them what will not be graded. At this point, we help them realize that the effectiveness of their final design isn't part of their grade. We explain that if students desire a grade of an A, they need to document their designs with diagrams and record their experimental results.

Table 6.3 Engineering Project Ideas Based on the Four NGSS Disciplines

NGSS disciplines Engineering project idea
Physical Sciences: law of conservation of mass Shrink polystyrene to build a scale model of the classroom, measure the mass of the polystyrene before and after shrinking
Physical Sciences: chemical bonds, activators, polymers Build the strongest bridge (determined by the mass of pennies held) that is made out of slime; students decide how to make the slime
Physical Sciences: sound waves Develop a structure that has the most efficient soundproofing
Physical Sciences: air pressure Build a wind car that can travel a set distance the fastest, powered only by a fan that mimics wind
Physical Sciences: insulators, exothermic, endothermic Design a cooler that keeps food warm or cold
Earth Sciences: solar energy Build a solar oven that can cook hot dogs or make s'mores to eat
Earth Sciences: filtration Create a filtration system that turns polluted water into drinking water
Life Sciences: seed dispersal (can integrate physical science) Build a device that can disperse a seed the farthest via wind
Life Sciences: osmosis Develop a membrane that is selectively permeable for some solute but not others
Technology, Engineering, and Applications of Science: erosion (can integrate life sciences or earth sciences) Design a mechanism that reduces soil erosion to benefit farmers and their crops
Technology, Engineering, and Applications of Science (can integrate physical sciences or earth sciences) Design a new technology for the International Space Station; it must be composed of materials that are lightweight and its parts must be easily replaceable

ENGINEERING PROJECT IDEAS

Table 6.3 lists engineering projects ideas based on the four NGSS disciplines. See the Technology Connections section for online links to additional resources.

See Chapter 12: Strategies for Incorporating the Arts and Kinesthetic Movement for a specific lesson plan that integrates a historical case study (the story of Filippo Brunelleschi) and the engineering process.

DIFFERENTIATION FOR DIVERSE LEARNERS

When we create groups for engineering tasks, we first take an inventory of the number of supplies we have available. The availability of materials will often be our limiting factor and will dictate the size of the group. If we have ample supplies, then we create groups of two or three because we want every student involved in the task in order to maximize each student's ideas and strengths. See Chapter 2: Strategies for Teaching Lab Procedures for resources to purposefully group students who require extra support.

The most difficult task for students is remembering to document all of their changes throughout the process. Students become very engaged during the testing and redesigning process and often forget about the required documentation. We find this to be especially true for students who don't enjoy writing. To help them, we make an effort to check on every group throughout the process, specifically asking to see their documentation. When we find students who haven't been documenting their results and redrawing their diagrams, we help them backtrack their steps so they can catch up. Once everyone in the group has completed their documentation, we allow the group to continue.

To support English language learners, we provide sentence frames to help them organize their data and design planning. See Figure 6.5: Mousetrap Catapult Sentence Frames for an example of sentence stems that can be used during the engineering process. We provide a copy of the sentence starters to students prior to testing their prototypes. As they document their answers in their lab notebook or on their lab worksheet, they choose the sentence that best supports their writing. They copy their chosen sentence and fill in the blanks with the details. They may use a sentence multiple times and may not use other sentences. They have the choice depending on the documentation they are tracking as they progress through the testing and redesigning steps.

Student Handouts and Examples

  • Figure 6.1: Student Examples of Mousetrap Catapult Designs
  • Figure 6.2: Mousetrap Catapult Lab Worksheet (Student Handout)
  • Figure 6.3: Mousetrap Catapult Picture
  • Figure 6.4: Mousetrap Catapult Rubric (Student Handout)
  • Figure 6.5: Mousetrap Catapult Sentence Frames (Student Handout)

What Could Go Wrong?

CLASSROOM MANAGEMENT

There are many moving parts during a lesson plan that uses the engineering process. Students are working in small groups, materials are being added and removed from designs, students are documenting ideas and results, and prototypes are being tested. To mitigate off-task and inappropriate lab behavior, we always review our behavioral expectations, focusing on the rule that horseplay is not permitted. See Chapter 2: Strategies for Teaching Lab Procedures for resources that help teach students lab rules and expectations.

We also ensure every person in the group has a responsibility. For example, in a group of three, tasks can be divided like this:

  • Task 1: Scribe—documents all changes and experimental results (now only one student in the group must document, not every student)
  • Task 2: Materials Engineer—manages the provision, use, and clean-up of all lab materials
  • Task 3: Lead Engineer—ensures all other group members are on task and facilitates respectful group conversations

Additionally, we walk around the room, guiding students so they are productive and actively participating. If students need to use a different type of location, such as a staircase or field, during Step 6: Test the Prototype, we prefer to have additional adults to help manage student behavior. For example, administrators, office staff, and parents have proven to be helpful assistants. If a classroom consists of a co-teacher, the two teachers can use the co-teaching strategy called Parallel Teaching, which divides a class into two groups and assigns each of the teachers to one of the groups. See Chapter 18: Strategies for Co-Teaching for resources and ideas about how to co-teach with a second adult.

An additional idea is to pair up with another teacher who is also teaching the engineering process. The groups who are still documenting ideas and building their prototypes work in one classroom and the groups that are testing their prototype work in a separate space. Each of the two educational environments can be monitored by one of the cooperating teachers.

MOUSETRAP DANGERS

Regardless of how much practice students are given, it is possible that a student will snap a mousetrap on one of their fingers. We've never seen a mousetrap break the skin but, if it was to happen, we would follow our school's protocol for how to assist an injured student. If students aren't comfortable setting the mousetraps, we always make ourselves available and volunteer to set the mousetraps for them.

Technology Connections

We have a few favorite online resources for egg drop challenges. Northeastern University's Center for STEM Education (https://stem.northeastern.edu/programs/ayp/fieldtrips/activities/eggdrop), provides differentiation for younger and older students. Buggy and Buddy provide printables, procedures, and extensions for egg drop challenges at “Egg Drop Challenge and Free Planning Printable” (https://buggyandbuddy.com/egg-drop-challenge-and-free-planning-printable-science-invitation-saturday).

Table 6.4 Pringle Potato Chip Challenge Rubric

Intactness Description Chip score
Perfectly intact Like it just left the factory 100 Points
Slightly damaged Cracked, but still in one piece 50 Points
Chipped chip Broken along the edges, but less than five pieces 20 Points
Split chip The chip is broken into two fairly equal pieces 10 Points
Significantly damaged Chipped and/or cracked into less than 20 pieces 5 Points
Pringle dust Too many pieces to count (more than 20) 1 Point

The Pringle potato chip mail challenge requires students to create a package that can safely transport a single chip through the US Post Office without cracking or chipping. Students can send the chip to themselves, but for additional fun, two schools from across the country can send their chips to each other. The official challenge rules, which originated from Charles Lindgren, can be found on Brian Bortz's website “Pringles Challenge” (https://sites.google.com/site/newpringleschallenge/rules). Bortz's site also includes Table 6.4: Pringle Potato Chip Challenge Rubric, which is copied here.

Bortz no longer matches schools so we use social media to find teachers who want to participate in the challenge and are located outside of our state. Larry Ferlazzo includes a list of resources that help teachers match their class with other classes. The resources are available in his blog entitled “The Best Ways to Find Other Classes for Joint Online Projects” (http://larryferlazzo.edublogs.org/2009/05/30/the-best-ways-to-find-other-classes-for-joint-online-projects).

For student examples and additional links to other Pringle potato chip mail challenge resources, see Peggy Reimers's blog at “The Pringles Challenge: A Fun-Filled Stem Activity” (https://blog.tcea.org/pringles-challenge-stem-activity).

For additional ideas of how to incorporate the engineering process into a K-8 classroom, we recommend Engineering Is Elementary (http://www.eie.org). For 4–12 classrooms, we suggest Try Engineering (https://tryengineering.org) and for K-12 resources we like Teach Engineering (https://www.teachengineering.org).

For specific engineering videos, such as the science of football, golf, and the Olympic Games we recommend NBC Learn (https://www.nbclearn.com/portal/site/learn/resources).

Attributions

Thank you to Annika McPeek and Hailey Quick for allowing us to use their examples of mousetrap catapult designs.

Thank you, Brian Bortz, for providing the directions and rubric for the Pringle potato chip mail challenge.

Thank you to Jeff Sesemann who gave us the ideas for some of the physical science engineering activities.

Figures

Pencil sketch showing the first two steps of how to draw a Mousetrap Catapult design.
Pencil sketch showing the fifth step of how to draw a Mousetrap Catapult design.

Figure 6.1 Student Examples of Mousetrap Catapult Designs

Figure 6.2 Mousetrap Catapult Lab Worksheet (Student Handout)

Photo illustration of a basic Mousetrap Catapult made using a mousetrap and a plastic spoon.

Figure 6.3 Mousetrap Catapult Picture

Figure 6.4 Mousetrap Catapult Rubric (Student Handout)

Figure 6.5 Mousetrap Catapult Sentence Frames (Student Handout)