Have you ever heard the phrase, “Light carries information?”  Think about a street signal light.  What does the green light mean for a driver?  A green light tells the driver that he or she can drive through an intersection.  It implies that drivers at the adjacent lights are stopped and waiting for their lights to turn green.  In other words, light can carry information about certain conditions in the world around us.  Warning lights come in a variety of colors and types depending on the intended purpose and where it is used.  In this unit, students learn about the use of warning lights in the U.S. and in other countries.  They build simple models of the electromagnetic spectrum to understand how everyday objects emit different wavelengths of light.  Students investigate the relative transmission of light through paper coated with various amounts of fat.  Students explore the reflective properties of materials in a laser targeting activity.  The unit culminates in a design challenge where students use their knowledge of the EM spectrum, reflection, and transmission to design an adjustable early warning device that transmits light across a distance.  Students develop a supported argument and presentation for how their warning light can be used in a specific country.

Educational outcomes

  • Lesson One: Students build empathy by researching warning light colors for the U.S. and 3-4 other countries
  • Lesson Two: Students build and use EM spectrum models to learn the types of devices that emit light of various wavelengths and frequencies
  • Lesson Three: Students conduct an investigation on a variety of samples to determine which one has the highest amount of fat based on the relative amount of light transmitted through the samples
  • Lesson Four: Students build a hinge-mirror kaleidoscope and investigate the reflective properties of materials to strike a target with a laser beam
  • Lesson Five: Students engage in a design challenge to build a light-based early warning system

STEAM INTEGRATION

Lesson One focuses on the use of color to convey meaning.  Students learn the significance of different colors (frequencies) of light used in warning lights.  Students develop and use models in Lessons 2-3 to investigate different scientific relationships (frequency and color, transmission of light through materials, and the ability of materials to reflect light).  Students literally get multiple perspectives on objects in Lesson 4 by creating kaleidoscopic effects using hinged mirrors to form angles through which to reflect light in different directions (MS-PS4-2).  Students bring the learning together in an engineering design challenge that develops a solution with real applications.

Click on the “+” icon to open each section

Unit Materials

  • RAFT Makerspace-in-a-Box Kit
  • RAFT Spectrum Bracelet Kit
  • Light bulbs, 1.5 volt
  • Alligator clips
  • Batteries, AA
  • Tape
  • Aluminum foil
  • Mylar sheets or strips
  • Tissue paper, newspaper, or equivalent
  • Laser pointers, 5 megawatt, green or red
  • Condiments or equivalent food samples containing various amounts of fat

 

Design Thinking Overview

Our design thinking units have five phases based on the d.school’s model. Each phase can be repeated to allow students to re-work and iterate while developing deeper understanding of the core concepts. These are the five phases of the design thinking model:

EMPATHIZE: Work to fully understand the experience of the user for whom you are designing.  Do this through observation, interaction, and immersing yourself in their experiences.

DEFINE: Process and synthesize the findings from your empathy work in order to form a user point of view that you will address with your design.

IDEATE: Explore a wide variety of possible solutions through generating a large quantity of diverse possible solutions, allowing you to step beyond the obvious and explore a range of ideas.

PROTOTYPE: Transform your ideas into a physical form so that you can experience and interact with them and, in the process, learn and develop more empathy.

TEST: Try out high-resolution products and use observations and feedback to refine prototypes, learn more about the user, and refine your original point of view.

The Design Thinking Process | ReDesigning Theater. (n.d.). Retrieved April 2, 2016, from http://dschool.stanford.edu/redesigningtheater/the-design-thinking-process/

STEAM Integrated Standards

NGSS Middle School Physical Science: MS-PS4-2

Develop and use a model to describe that waves are reflected, absorbed, and transmitted through various materials.

Suggestions for pacing and differentiation

Lessons 1-2 can combined to focus on the application of color (light frequencies).  Lesson 3 can be positioned as part of a unit on light, nutrition, macromolecules, and/or energy.  Lesson 4 can be used to teach students about virtual images created using lenses and mirrors.

Lesson Overview

In this lesson students develop empathy by learning how other countries convey warnings to their citizens using lights and then make a comparison with warning light usage in the Unites States.  They create a handy reference chart that compares usage between four countries of their own choosing, allowing them to identify patterns between colors, styles, and conventions in warning lights and the intended use for each particular color or style.

Essential Questions:

  • How do other countries convey warning messages using lights?
  • How do the meanings for specific color warning lights in the U.S. compare to those in other countries?

LESSON PROCEDURE:

  1. Students choose four different countries on which to conduct research and record the country names in the Maker Journal page.
  2. Students find websites containing information on warning lights for each country AND the United States.  They may start with the websites in the External Resources section (see right margin of this page).
  3. Students complete the table in the Maker Journal page.  This will serve as a reference chart.
  4. Students use the reference chart to describe why each color of warning light is well-suited for its function in conveying a specific meaning.

Student Direction (Click + to open)

Sample teacher and student dialog.

T: Show students images of different emergency warning lights.  You may want to select images from a Google image search on the topic.  “What is the purpose for these kinds of lights?  Is there a special use for each color?  What do they mean?”

S: “Police use red and blue.”  “They tell people to move out of the way!”

T: “We are going to conduct web research to inquire about the purpose for different colors of emergency/warning lights.  We will do this for lights used in the U.S. and four different countries.  Let’s think of ways that we could look for this information.”

S: “Wikipedia, Google search, resources in the library”

T: “Wikipedia and Google can provide lots of information.  Remember to use the rule of three, where you compare three sources of information on a topic to check for consistency.  What else might help make sure the information you find is trustworthy?”

S: “We should find websites from schools, governments, or ones that end with .org.”

T: “Use your Maker Journal page to record your findings.”

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Concept Quick Reference (Click + to open)

Light waves, or electromagnetic waves, do not require a medium in order to propagate (travel outward from the source).  They can travel through a vacuum (space with no air or other matter).  This is in contrast to matter waves which must move through matter in order to propagate.  For example, after a rock is thrown into a pond we observe matter waves rippling outward through the water.  When waves propagate they carry energy from one place to another.  All waves have the properties show in the graphic below.  The amplitude of a wave is the maximum extent of a vibration or oscillation, measured from the position of equilibrium.  These are the crests and troughs of a wave.  The wavelength is the distance between successive crests of a wave.  The frequency of a wave is the rate at which the crests or troughs reach or pass a certain point t per second (see below).  Frequency is usually measured in Hertz (1 Hz = 1 wave per second).

waves

frequency

White light contains all of the colors of the rainbow, remembered as the familiar acronym ROYGBV for red, orange, yellow, green, blue, and violet (purple).  These are the colors of light we can see.  When white light shines on an object and the object appears to be red, it is because the material in the object absorbs all of the colors of light except red, which is reflected off the object.  This red light enters our eyes and is interpreted by our brain as red.  Color filters are transparent materials that only absorb and transmit  (allow to pass through) certain colors of light.  The transparent covers on most warning lights are examples of color filters.  For example, a warning light with a blue transparent cover appears blue because the material that makes up the cover absorbs all of the colors of light except blue, which passes right through and enters our eyes.  Light appears as different colors due to the frequency.  In general, the colors of light represented in ROYGBV increase in frequency moving from red to violet (see frequency diagram above).

Lesson Materials

Tech

  • Computers or mobile devices
  • Internet access

Maker Journal Pages

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Teacher Notes

Consider selecting a few images of different emergency vehicle lights or other warning lights such as those used in harbors or construction sites.  Model good techniques for safe quality internet searches.  Consider pre-selecting sites that yield quality information for this topic.

Learning Targets

  • Students will develop a reference chart as a model to describe that light can be transmitted in different colors to convey specific information.

Assessment

Student Self Assessment

Student groups review their Maker Journal page and summarize their learning in a group discussion.

Peer Assessment

Student groups discuss and compare their findings on the types of warning light colors for each country.

Teacher Assessment

Conduct a whole group discussion to allow all students to share, discuss and compare their findings around different designs and uses for warning lights.  Have students discuss why they think certain colors of warning lights tend to hurt our eyes more than others.

Lesson Overview

This lesson focuses on the structure and information represented in the electromagnetic spectrum.  Most students think of light only in terms of visible light, which we can observe directly with our eyes.  The spectrum contains other forms of light such as infrared and x-rays, and these forms differ in the amount of energy they carry, their wavelengths, and their frequencies.  These differences are the reason behind the arrangement of the spectrum.  To understand these concepts, students will assemble a bracelet as a model of the spectrum.  The bracelet is a mnemonic device that helps students remember the position and order of the types of light along the spectrum.  Knowledge of the electromagnetic spectrum is important for understanding the properties of light waves that are reflected, absorbed, or transmitted through objects (MS-PS4-2).  Students will conduct web research to identify devices or applications for each range of wavelengths represented in the EM spectrum.

Essential Questions:

  • Why is the EM spectrum arranged as it is?
  • How is the frequency of a light wave related to its wavelength?
  • How can the spectrum bracelet be used to describe instances where light is reflected or absorbed?

LESSON PROCEDURE:

  1. Students use the spectrum chart in the Maker Journal page to individually assemble their spectrum bracelets.
  2. Students conduct web research to find information on devices or specific uses for each wavelength range represented in the spectrum.
  3. Students record their findings and then answer the questions in the Maker Journal pages for the lesson.

Student Direction (Click + to open)

Sample teacher and student dialog.

T: Ask students these questions: “What do you think radio waves look like?  Do they have color?  What color are they?  Can we see them?  How do you know?”

S: “They are white.”  “Radio waves are invisible.”  “They are grey!”

T: “We are going to do two things.  First we will build a model of something called the electromagnetic spectrum, or simply the EM spectrum.  This is a representation of all types of light waves, even the ones we can’t see.  After that we will conduct web research to find information on the different applications, or uses, for each type of light.  The different types of light are based on the wavelength for each light wave type.  Where might we find this information?”

S: “Wikipedia, physics websites, college sites, Google!”

T: “I have selected some websites for you to start with and then you can find more.  Remember to use your Maker Journal page to record your findings.”dl-student


Concept Quick Reference (Click + to open)

Electromagnetic radiation, or “light”, is a form of energy that includes radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.  The spectrum includes wavelengths that humans can see (visible light) and also wavelengths that humans cannot see.  The visible portion of the spectrum includes many different colors, expressed in terms of frequency or wavelength.  Red light, for example, has a lower frequency and longer wavelength than blue light.

Many objects in the universe radiate at wavelengths that our eyes cannot see. Astronomers study these objects with telescopes and other instruments that can detect their wavelengths. Different devices are built to detect different wavelengths of light energy.

To remember the order of the colors in the visible part of the electromagnetic spectrum (Red, Orange, Yellow, Green, Blue, Violet), the mnemonic “ROYGBV” is often used (see below).  Mnemonics are memory aids.  Other parts of the electromagnetic spectrum cannot be perceived by unaided human eyes because their wavelengths are either longer or shorter than the visible light waves.  Wavelengths that are longer than visible light waves include radio and TV waves, microwaves, and infrared radiation.  Wavelengths that are shorter than visible light waves include ultraviolet, x-rays, and gamma rays.

spectrum

Lesson Materials

Building Materials

Maker Journal Pages

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Teacher Notes

Remove the Idea Sheets from the kits so students use the information in the Maker Journal pages to assemble the bracelets.  Have students work in groups but assemble their own bracelets so each student has one.

Learning Targets

  • Students will assemble a model of the electromagnetic spectrum to describe that light waves are reflected or absorbed by various materials

Assessment

Student Self Assessment

Students compare their spectrum bracelets to the order of bead colors in the chart and make corrections as necessary.

Peer Assessment

Students discuss and share their findings on devices or uses for each wavelength of light.

Teacher Assessment

Review student responses to the questions in the Maker Journal pages and provide guidance as necessary.  Hold a whole group discussion around the uses for each wavelength of light represented in the spectrum.  Discuss the arrangement of light along the spectrum in terms of wave properties (amplitude, frequency, wavelength).

Lesson Overview

Students conduct an investigation where they observe the transmission of light through paper containing different food samples, each containing various amount of fat (MS-PS4-2).  Students explain the relative amounts of translucence in terms of the fat content in the samples and how it allows light to be transmitted through the paper.  Then students develop a hypothesis for how the investigation can be used to help people make healthier food choices.

Essential Question:

  • How can investigating the amount of light transmitted through a material be useful for improving your health?

LESSON PROCEDURE:

  1. Students obtain 10 food samples from designated area and put 10 ml (2 teaspoons) of each sample in a labeled portion cup and then bring the cups to their tables.  Use permanent markers for labeling the cups #1-10.
  2. Students use cotton swabs to smear food samples onto the Trimming the Fat Data Sheet.  They dip a swab into each labeled sample and smear it onto the corresponding square in the data sheet.
  3. Students wipe off the excess material from the square with a paper towel.
  4. Students repeat these steps for all food samples, using a different swab for each sample to avoid cross-contamination.
  5. Allow time for the smeared samples to fully dry.
  6. Students hold the dry data sheet up to a light source and record observations in the Maker Journal page.

Suggestions for Food Samples:

Low-Fat or Fat Free: Low-fat / fat free salad dressing, sour cream, ketchup, mustard, hummus, soy sauce, chili sauce

Higher Fat: Butter, regular sour cream, peanut butter, mayonnaise, cooking oil, dish soap

Student Direction (Click + to open)

Sample teacher and student dialog.

T: Show students different pictures of condiments such as butter, cooking oil, ketchup, mustard, or low-fat salad dressing.  Google Image search is a useful tool.  “If we were to shine a light on these foods, which one(s) do you think would allow the most light to shine through?  How might we figure this out?”

S: “The cooking oil is more clear.”  “The butter blocks the light like a wall does.”

T: “We are going to conduct an investigation to see how much light can pass through various food samples.  Then we will determine which food sample has the most fat in it based on the results.  Finally, you will develop a hypothesis for how conducting an investigation like this can help you make healthier food choices.”

S: “Will you give us the samples?”

T: “You will gather the food samples from the designated table and follow the instructions in your Maker Journal page.  I will be circulating to answer questions and provide assistance as needed.”dl-student


Concept Quick Reference (Click + to open)

There are 4 types of organic, biological macromolecule “building blocks”: lipids, proteins, carbohydrates, and nucleic acids (e.g., DNA, RNA).  All lipids are hydrophobic, meaning they repel water rather than attract or absorb water.  Fats and oils, waxes, and steroids are all lipids.  Lipids perform essential biological functions including forming cell membranes and storing energy.  Lipids are part of the essential vitamins and hormones needed to keep the human body healthy.  Although lipids are important for maintaining good health, consuming too many foods high in fat can lead to health issues such as heart problems and obesity.  This makes it important to know how much fat is in certain foods.  The amount of fat in some foods might surprise you!  In this lesson students test different food samples for relative amounts of fat using the transmission of light as an indicator.

Paper contains many tiny voids that are filled with air.  The paper fiber-air boundaries scatter (reflect) much of the incoming light making the paper opaque, meaning you cannot see through it.  Oils and fats can fill the voids between the paper fibers when rubbed on the paper.  Light striking the soaked area will scatter less and be transmitted more, making the area translucent, meaning you can see through the paper but cannot make out every detail behind it (see below).

fat

 

Lesson Materials

Building Materials

  • Portion cups, 2 oz.
  • Cotton swabs
  • Food samples for testing
  • Paper towels or napkins

Other

  • Permanent markers

Maker Journal Pages

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Teacher Notes

Arrange all food samples in a location safely accessible to all student groups.  Avoid bottlenecks where students cluster and hold up others from accessing food samples.  One method is to only allow 1-2 people from each group to choose samples for their teams.

Active Classroom

Encourage students to suggest or even bring in specific spreadable foods to class for everyone to use in the investigation.

Practice and predict clean-up strategies before beginning the activity. Ask students to offer suggestions for ensuring that they will leave a clean and useable space for the next activity. Students may enjoy creating very specific clean-up roles. Once these are established, the same student-owned strategies can be used every time hands-on learning occurs.

Learning Targets

  • Students will investigate the fat content in different foods and use the results as a model to describe that light waves are transmitted through certain materials.

Assessment

Student Self Assessment

Student groups summarize their learning about the relationship between light transmission and the relative amount of fat in each food sample.

Peer Assessment

Student groups discuss and compare their findings around the samples they think contain the most fat based on how translucent each sample appears.

Teacher Assessment

Conduct a whole group discussion to allow all students to share their responses to the analysis questions and discuss different applications of this investigation to improve health and inform personal food choices.

Lesson Overview

Students build a hinged mirror to explore the effect of geometry on reflected light in terms of the virtual images seen in the mirror.  Then students will investigate the reflective properties of different materials by reflecting a laser beam around obstacles in order to strike a target (MS-PS4-2).

Essential Questions:

  • How does geometry affect the way light waves are reflected?
  • How can materials be used to transmit reflected light to an intended target?

LESSON PROCEDURE:

  1. Student groups gather materials to conduct the hinged mirror kaleidoscope exploration.
  2. Students assemble the kaleidoscopes by cutting reflective material into equal size sheets and taping them together, forming a hinged mirror (see below).
  3. Students observe and record the number of virtual images seen in the mirror for various angle measures in the Maker Journal page.
  4. Student groups discuss and answer the first essential question above for the lesson.
  5. Students identify and gather reflective materials and laser pointers from materials station.
  6. Students build a course in which to shine the laser beam off several reflective surfaces and towards a target.  They may view the videos in the External Resources section for ideas.
  7. Student groups discuss and answer the second essential question above for this lesson.

Student Direction (Click + to open)

Sample teacher and student dialog.

T: Show students images of light reflecting off a surface.  You can use Google image search to find images.  “What is happening to the light beam?  What is it about the surface of the object that causes this to happen to the light beam?”

S: “It’s being reflected.”  “The light is bending!”  “The surface is like a mirror, reflecting the light instead of absorbing it.”

T: “How can light be made to move around obstacles and strike a target?  We are going to explore this question in two different ways.  First, we will make a simple kaleidoscope so that we can explore how different angles measurements affect the reflection of light.  Then, we are going to design a “laser obstacle course” so a laser beam can change direction and hit an intended target.  Why might doing this be important in the real world?”

S: “How are we going to design the course?”  “In the real world a car might need to be warned about a hazard before turning a corner.”

T: “You will identify materials that you think are reflective and test their ability to reflect the beam.  Then you will incorporate several of these surfaces into the course, moving and adjusting them until the laser beam strikes the target that you must place at the end of the course.”  “That is a great example!”dl-student


Concept Quick Reference (Click + to open)

We see an object when light is reflected and transmitted from the object and travels to our eye.  When an object is between two hinged mirrors, light from the object bounces back and forth between the mirrors before it reaches the eye.  The general rule for a reflected light wave, represented as a ray, is “angle in = angle out” (see below).  An image is formed each time the light bounces off a mirror.  The number of images seen in a pair of hinged mirrors depends on the angle measure formed between the mirrors.  As the angle between the mirrors is made smaller, the light reflects back and forth more times, and more virtual images of an object can be seen.

The word “laser” is actually an acronym that stands for light amplification by stimulated emission of radiation.  A laser is created when the electrons in atoms in special glasses, crystals, or gases absorb energy from an electrical current or another laser and become “excited”, or energized.  There are many types of lasers.  Solid-state lasers have lasing material distributed in a solid matrix such as a ruby laser emitting infrared light.  Gas lasers such as a common helium lasers have a primary output of visible red light.  Carbon dioxide lasers emit energy in the far-infrared and are used for cutting hard materials.  Excimer lasers use reactive gases, such as chlorine and fluorine, mixed with inert gases such as argon, krypton or xenon.  A laser pointer or laser pen is a small handheld device with a power source (usually a battery) and a laser diode emitting a very narrow coherent low-powered laser beam of visible light, intended to be used to highlight something of interest by illuminating it with a small bright spot of colored light.  Laser beams can be reflected like any other form of light (see below).

           

Lesson Materials

Building Materials

Connecting Materials

  • Tape
  • Binder clips

Other

  • Laser pointers, 5 megawatt
  • Batteries, AA or AAA depending on the laser pointers used

Maker Journal Pages

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Teacher Notes

Materials: Put all building materials on a table or cart and position it so that all student groups have safe and equal access.  Only 1-2 people per group need to gather materials for their groups.

Space: The laser targeting activity may require space.  Consider moving furniture around to optimize the space for arranging reflective surfaces in different configurations.

Lasers: Remind students to avoid shining lasers into the eyes!

Active Classroom

Students need to have opportunities to select their own building materials and to seek and explore content with minimal guidance from the facilitator.  Although this lesson uses laser pointers, this should not be a point of anxiety for the facilitator.  Students internalize the concept of reflection more efficiently if they can actually see beams of light changing direction and if they can measure angles of incidence.

Learning Targets

  • Students will use a hinged mirror kaleidoscope as a model to describe the reflection of light in terms of geometry
  • Students will manipulate a laser beam by reflecting it and striking a target and then describe its path

Assessment

Student Self Assessment

Ask students to rate their level of understanding of reflection in terms of geometry from 1-5, 5 being the highest level of understanding.  Students explain their reasons for assigning the rating.

Peer Assessment

Student groups discuss and compare their laser beam courses and steps for striking the target

Teacher Assessment

Review Maker Journal pages and ask students to demonstrate how the angle of reflection can alter the path of light

Design Challenge Overview

In the culminating project, student groups demonstrate their knowledge of reflection, absorption, and transmission of light waves by designing, building, and testing an adjustable early warning device that transmits light across a distance.  They engage in each step of the design process and reiterate multiple times until their group agrees the device meets the defined criteria and constraints for the project (see design challenge introduction).  Students then develop a presentation describing how their warning light can be used in the countries they researched in Lesson One.

Essential Questions:  

  • How can we build a device with an adjustable light beam out of various materials that uses the reflection, absorption, and transmission of light to convey an early warning message to users?
  • Which country will be the most likely to use such as device and why?

LESSON PROCEDURE

  1. Students facilitate a brainstorm in their groups to generate approaches to answer the essential questions.
  2. Student groups agree on an idea from the brainstorm and then select materials with which to build their first prototype.
  3. Students build a prototype according to the criteria and constraints defined in the design challenge introduction (see section below).
  4. Students test their first prototype using the checklist provided in the Maker Journal page, noting any changes or modifications that must be made.
  5. Students reiterate, repeating the process until the group agrees that the device successfully meets the criteria and constraints.
  6. Student groups demonstrate how to operate their devices and conduct a presentation describing why the devices would likely be used in a specific country based on preliminary research conducted in Lesson One (empathy phase).

Introduce the Design Challenge (Click + to open)

Sample student & Teacher Dialog.

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T: Introduce the design challenge: “Today you will be combining the learning from the previous lessons on absorption, reflection, and transmission of light waves to solve a problem through design.  Here is the problem: How can we build an adjustable device out of various materials that uses the reflection, absorption, and transmission of light to convey an early warning message to users?”

S: “How will we do it?”

T: “There are many designs for building such an early warning device, but keep in mind it must be useful to the country you researched.  You found information on specific types of warning lights, including color, shape, and other attributes.  Think about the kind of warning message the device must convey, how it might convey the message before a specific hazard occurs, and how to make it adjustable and easy to use by the intended user.”

S: “This sounds very cool!”

Criteria & Constraints

Review the criteria and constraints with students.  Engineers design things using some rules about how the designs must behave or work.  These rules are called criteria.  Engineers can run out of materials, money, time to build, or space in which to build something.  In other words there are limits on how something can be built.  These limits are called constraints.  The criteria and constraints for this challenge are below.

Criteria (design requirements) Constraints (design limitations)
  • Device uses specific colors of light
  • Device includes components for transmitting light
  • Device includes components for absorbing light
  • Device includes components for reflecting light
  • Device includes adjustable light beam
  • Device can convey warning message from at least 100 ft. away
  • Device must be built with materials provided
  • Device must be completed and tested in the given time
  • Device must include 8-12 different materials in addition to fasteners and/or adhesives
  • Device must be battery-powered

Ideate
Student groups will leverage their learning on the properties of light (frequency, color, wavelength), reflection, absorption, transmission, and on specific types of warning lights to brainstorm and sketch ideas for an adjustable early warning system and methods for testing it against the defined criteria and constraints.  Students may choose or need to return to this phase as they iterate.

Student Directions (Click + to open)

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T: “Some of you may spend too much time figuring out how to start.  Be sure to get something built quickly so that you have a real version of the idea you started with.  Engineers call this rapid prototyping.  Your first iteration will not be the best or final one, so don’t be too concerned with making it perfect!”

S: “I want it to work the first time.”  “How will we know if it works well?”

T: “You will test the prototype once your group agrees it’s ready.  You will check to see if it meets the criteria and constraints and most likely come back to prototyping based on what you learn through testing.  This is what iteration is all about.”

S: “Oh, this means we will build more than once.  I get it.  It’s a cycle!”

Prototype

Student groups choose materials and begin build the first iteration of their early warning device based on an idea generated during the ideate phase.  Keep in mind students may choose to or need to return to this phase as the iterate further.

Student Directions (Click + to open)

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T: “You will need to test your design against the criteria and constraints to ensure the device works properly and can be used to address the design problem.  The checklist in the Maker Journal page will provide a quick way to evaluate your design.  Be sure to record everything you observe.”

S: “When will we start testing?”

T: “Your group will test the prototype as soon as you all agree it is ready to be tested.  I do not need to tell you when to start.  Make sure you are consistent in the way you evaluate your design for each test.”

S: “How will we know when to stop testing?  When is the design final?”

T: “When your group agrees the device meets all criteria and constraints and has been improved as much as possible in the time given, you can stop.  I may ask questions or make suggestions for things that can be added or modified and, if time permits, you may decide to address them.”

Test your Design

Student groups test their designs for the ability to meet all criteria and constraints using the checklist in the Maker Journal page.  They record their observations for each test and use the data to refine the design as they continue to iterate.

Student Directions (Click + to open)

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T: Provide a general description of what students will do during and after the design challenge.  “You will be engaging in each of the steps of the engineering design process in order to solve a design problem.  The steps of the process are ideate, prototype, and test.  We’ll go through these steps many times to produce the solution to the problem.  After you develop the final iteration of the solution, your group will demonstrate for the class how to use it and present how the device can be used by people in a specific country.  You can use the presentation rubric to help develop a solid presentation!”

S: “Why is it necessary to link the solution to a specific country?”

T: “Empathy is about understanding different perspectives.  Engineers design solutions to problems with specific human or environmental needs in mind.  This is why they spend quality time developing empathy for the potential users of the design solution.  In this case we need to understand how a warning message might be perceived by a variety of users.  In reality, engineers work to develop solutions that can be used globally, so it is necessary to understand the perspective of people in a particular country as an exercise in designing with empathy.”

S: “That makes sense!”


Concept Quick Reference (Click + to open)

This design challenge allows students to engage in the engineering design process.  This process can be represented in many ways.  People may engage in the steps in any order.  This unit is built around a model with five design phases: empathy, define, ideate, prototype, and test (see Unit Overview margin for complete descriptions of each phase).  Engineering is an iterative discipline with many design steps being taken several times.  This is why there are so many versions of televisions, toothbrushes, and many other common items.  Each product is intended to serve a particular purpose and meet the needs of specific users.

This specific design challenge focuses on light-based warning messages as an example of light waves and provides students with an opportunity to combine knowledge of wave properties with the concepts of wave reflection, absorption, and transmission through various materials.  Students develop a real solution for the problem of conveying a warning message before an immediate hazard, much like a lighthouse warns ships on the sea, only this message must be perceived and understood by people in a specific country.  This is the real-world connection that circles back to the empathy lesson where students conducted research on warning lights and compared their findings to information on warnings specific to U.S.  It is an exercise in designing for a global market.

Design Challenge Materials

Building Materials

Connecting Materials

  • Tape
  • Binder clips

Other

  • Laser Pointers
  • Batteries, AA or AAA
  • Light Bulbs, 1.5V
  • Lenses, various types

Maker Journal Pages

dl-student

Teacher Notes

Consider having resources like books or the internet available for reference.  Students may need more information or examples on how to focus light using lenses and/or reflective surfaces

Active Classroom

Communication is critical in the design process. Students need to be allowed to talk, stand, and move around to acquire materials. Help students become successful and care for the success of others by asking them to predict problems that might arise in the active environment and ask them to suggest strategies for their own behavior that will ensure a positive working environment for all students and teachers.

Practice and predict clean-up strategies before beginning the activity. Ask students to offer suggestions for ensuring that they will leave a clean and useable space for the next activity. Students may enjoy creating very specific clean-up roles. Once these are established, the same student-owned strategies can be used every time hands-on learning occurs.

Learning Targets

  • Students will design, build, and test a device that includes elements that reflect, transmit, and absorb light waves
  • Students will use the device to describe each instance of reflection, absorption, and transmission of light and the properties of specific materials responsible for each

Assessment

Student Self Assessment

Students review their Maker Journal page for evidence that they understand the properties of light waves and can individually explain where waves are being reflected, absorbed, and transmitted in the group device.

Peer Assessment

Allow student groups to conduct a “gallery walk” where they explore and learn about each other’s devices.

Teacher Assessment

Assess student presentations using the presentation rubric.