Students learn how to classify materials as mixtures, elements or compounds and identify the properties of each type. The concept of separation of mixtures is also introduced since nearly every element or compound is found naturally in an impure state such as a mixture of two or more substances, and it is common that chemical engineers use separation techniques to separate mixtures into their individual components. For example, the separation of crude oil into purified hydrocarbons such as natural gas, gasoline, diesel, jet fuel and/or lubricants.

This unit describes a general approach to guiding students to complete service-based engineering design projects, with specific examples provided in detail as associated activities. With your class, brainstorm ideas for engineering designs that benefit your community or a specific person in your community. Then, guided by the steps of the engineering design process, have students research to understand background science and math, meet their client to understand the problem, and create, test and improve prototype devices. Note that service-based projects often take more time to prepare, especially if you arrange for a real client. However, the authors notice that students of both genders and all ethnicities tend to respond with more enthusiasm and interest to altruistic projects.

The earliest explorers did not have computers or satellites to help them know their exact location. The most accurate tool developed was the sextant to determine latitude and longitude. In this activity, the sextant is introduced and discussed with the class. Students will learn how a sextant can be a reliable tool that is still being used by today's navigators and how computers can help assure accuracy when measuring angles. Also, this activity will show how computers can be used to understand equations even when knowing how to do the math is unknown.

Students use their understanding of projectile physics and fluid dynamics to find the water pressure in water guns. By measuring the range of the water jets, they are able to calculate the theoretical pressure. Students create graphs to analyze how the predicted pressure relates to the number of times they pump the water gun before shooting.

Students perform one of the first steps that environmental engineers do to determine water quality sampling and analysis. Student teams measure the electrical conductivity of four water samples (deionized water, purified water, school tap water and a salt-water solution) using teacher-made LED-conductivity testers and commercially available electrical conductivity meters. They use multimeters to also measure the resistance of the samples. They graph their collected data to see the relationship between the conductivity and resistance. Then, all students measure the conductivity of tap water samples brought to school from their homes; they organize and average their data by sub areas within their local school district to see if house location has any relationship to the water conductivity in their community.

By this point in the unit, students have learned all the necessary information and conceptualized a design for how an optical biosensor could be used to detect a target strand of DNA associated with a cancer-causing gene as their solution to the unit's challenge question. Now student groups act as engineers again, using a poster format to communicate and prove the validity of the design. Successful posters include a description of refraction, explanations of refraction in a thin film, and the factors that can alter the interference pattern of a thin film. The posters culminate with an explanation of what is expected to be seen in a biosensing device of this type if it were coupled to a target molecule, proven with a specific example and illustrated with drawings and diagrams throughout. All the poster elements combine to prove the accuracy and viability of this method of gene detection. Together with its associated lesson, this activity functions as part of the summative assessment for this unit.

Student teams make polymers using ordinary household supplies (glue, borax, water). They experiment with the semi-solid material when warm and cold to see and feel its elastic and viscous properties. Students will begin to understand how the electrical forces between particles change as temperature or the force applied to the substance changes. Is it a solid, a liquid, or something in between? How might it be used?

Students build and use a very basic Coulter electric sensing zone particle counter to count an unknown number of particles in a sample of "paint" to determine if enough particles per ml of "paint" exist to meet a quality standard. In a lab experiment, student teams each build an apparatus and circuit, set up data acquisition equipment, make a salt-soap solution, test liquid flow in the apparatus, take data, and make graphs to count particles.

In this activity, students are challenged to design a contraption using simple machines to move a circus elephant into a rail car. After students consider their audience and constraints, they work in groups to brainstorm ideas and select one concept to communicate to the class.

Students modify a provided App Inventor code to design their own diseases. This serves as the evolution step in the software/systems design process. The activity is essentially a mini design cycle in which students are challenged to design a solution to the modification, implement and test it using different population patterns The result of this process is an evolution of the original app.

Students examine collisions between two skateboards with different masses to learn about conservation of momentum in collisions.

Through this unit, written for an honors anatomy and physiology class, students become familiar with the human skeletal system and answer the Challenge Question: When you get home from school, your mother grabs you, and you race to the hospital. Your grandmother fell and was rushed to the emergency room. The doctor tells your family your grandmother has a fractured hip, and she is referring her to an orthopedic specialist. The orthopedic doctor decides to perform a DEXA scan. The result show her BMD is -3.3. What would be a probable diagnosis to her condition? What are some possible causes of her condition? Should her daughter and granddaughter be worried about this condition, and if so, what are measures they could take to prevent this from happening to them?

Students will learn about bone structure, bone development and growth, and bone functions. Later, students will apply this understanding to answer the Challenge Question presented in the "Fix the Hip" lesson and use the acquired learning to construct an informative brochure about osteoporosis and biomedical engineering contributions to this field.

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.

Students learn about two types of friction static and kinetic and the equation that governs them. They also measure the coefficient of static friction experimentally.

In this hands-on activity, students learn about two types of friction static and kinetic and the equation that governs them. They also measure the coefficient of static friction and the coefficient of kinetic friction experimentally.

Students use a spring scale to drag an object such as a ceramic coffee cup along a table top or the floor. The spring scale allows them to measure the frictional force that exists between the moving cup and the surface it slides on. By modifying the bottom surface of the cup, students find out what kinds of surfaces generate more or less friction.

In this activity, students use an old fashion children's toy, a metal slinky, to mimic and understand the magnetic field generated in an MRI machine. The metal slinky mimics the magnetic field of a solenoid, which forms the basis for the magnet of the MRI machine. Students run current through the slinky and use computer and calculator software to explore the magnetic field created by the slinky.

Students learn why shock absorbers are necessary on vehicles, how they dampen the action of springs, and what factors determine the amount of dampening. They conduct an experiment to determine the effect of spring strength and port diameter on the effectiveness of a shock absorber. Using a syringe, a set of springs, and liquids of different viscosities, students determine the effects of changing pressures and liquids on the action of a model shock absorber. They analyze their data through the lens of an engineer.

To experience the three types of material stress related to rocks — tensional, compressional and shear — students break bars of soap using only their hands. They apply force created by the muscles in their own hands to put pressure on the soap, a model for the larger scale, real-world phenomena that forms, shapes and moves the rocks of our planet. They also learn the real-life implications of understanding stress in rocks, both for predicting natural hazards and building safe structures.