Students learn about the scientific and mathematical concepts around electromagnetic light properties that enable the engineering of sunglasses for eye protection. They compare and contrast tinted and polarized lenses as well as learn about light intensity and how different mediums reduce the intensities of various electromagnetic radiation wavelengths. Through a PowerPoint® presentation, students learn about light polarization, transmission, reflection, intensity, attenuation, and Malus’ law. A demo using two slinky springs helps to illustrate wave disturbances and different-direction polarizations. As a mini-activity, students manipulate slide-mounted polarizing filters to alter light intensity and see how polarization by transmission works. Students use the Malus’ law equation to calculate the transmitted light intensity and learn about Brewster’s angle. Two math problem student handouts are provided. Students also brainstorm ideas on how sunglasses could be designed and improved, which prepares them for the associated hands-on design/build activity.

Students apply what they know about light polarization and attenuation (learned in the associated lesson) to design, build, test, refine and then advertise their prototypes for more effective sunglasses. Presented as a hypothetical design scenario, students act as engineers who are challenged to create improved sunglasses that reduce glare and lower light intensity while increasing eye protection from UVA and UVB radiation compared to an existing model of sunglasses—and make them as inexpensive as possible. They use a light meter to measure and compare light intensities through the commercial sunglasses and their prototype lenses. They consider the project requirements and constraints in their designs. They brainstorm and evaluate possible design ideas. They keep track of materials costs. They create and present advertisements to the class that promote the sunglasses benefits, using collected data to justify their claims. A grading rubric and reflection handout are provided.

Student teams design and conduct quality-control experiments to test the reliability of several ultraviolet protection factors. Students use UV-detecting beads in their experimental designs to test the effectiveness of various types of sunscreens and sunblock. For example, they might examine zinc oxide nanoparticles versus traditional organic sun protection factors. UV intensity is quantitatively measured by UVA and UVB Vernier sensors, and students record and graph their results. By designing and conducting this experiment, students compare various substances, while learning about quality control.

In this activity, students learn how to prevent exposure to the Sun's harmful ultraviolet rays. Students will systematically test various sunscreens to determine the relationship between spf (sun protection factor) value and sun exposure. At the end of the activity, students are asked to consider how this investigation could be used to help them design a new sunscreen.

Students gain first-hand experience with the steps of the scientific method as well as the overarching engineering design process as they conduct lab research with the aim to create a bioplastic with certain properties. Students learn about the light mechanism that causes ultraviolet bead color change, observe the effect of different light waves on a phosphorescence powder, and see the connection between florescence, phosphorescence and wavelength. Students compose hypotheses and determine experimental procedure details, as teams engineer variations on a bioplastic solid embedded with phosphorescence powder. The objective is to make a structurally sound bioplastic without reducing its glowing properties from the powder embedded within its matrix. Groups conduct qualitative and quantitative analyses of their engineered plastics, then recap and communicate their experiment conclusions in the form of a poster, slides and verbal presentation. As an extension, teams make their own testing apparatuses. As a further extension, they combine all the group results to determine which bioplastic matrix best achieves the desired properties and then “manufacture” the optimum bioplastic into glowing toy figurine end products! Many handouts, instructions, photos and rubrics are provided.

In this unit students investigate the cause of sunburns, the function of sunscreen, and the ways in which chemists determine the molecular structure of matter by applying relationships about how light interacts with matter on an atomic or molecular level. 

Towards finding a solution to the unit's Grand Challenge Question about using nanoparticles to detect, treat and protect against skin cancer, students continue the research phase in order to answer the next research questions: What is the structure and function of skin? How does UV radiation affect the chemical reactions that go on within the skin? After seeing an ultraviolet-sensitive bead change color and learning how they work, students learn about skin anatomy and the effects of ultraviolet radiation on human skin, pollution's damaging effect on the ozone layer that can lead to increases in skin cancer, the UV index, types of skin cancer, ABCDEs of mole and lesion evaluation, and the sun protection factor (SPF) rating system for sunscreens. This prepares students to conduct the associated activity, in which they design quality-control experiments to test SPF substances.

Ultraviolet-visible spectroscopy or ultraviolet-visible spectrophotometry (UV-Vis or UV/Vis) refers to absorption spectroscopy or reflectance spectroscopy in the ultraviolet-visible spectral region. Ultraviolet-visible (UV-VIS) spectroscopy is an analytical method that can measure the analyte quantity depending on the amount of light received by the analyte.