Students design and create sensory integration toys for young children with developmental disabilities an engineering challenge that combines the topics of biomedical engineering, engineering design and human senses. Students learn the steps of the engineering design process (EDP) and how to use it for problem solving. After learning about the human sensory system, student teams apply the EDP to their sensory toy projects. They design and make plans within given project constraints, choose materials, fabricate prototypes, evaluate the prototypes, and give and receive peer feedback. Students experience the entire design-build-test-redesign process and conclude with a class presentation in which they summarize their experiences with the EDP steps and their sensory toy project development.

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 are introduced to the concepts of graywater and water reuse within households. They calculate the amount of used water a family generates in one day and use a model of home plumbing to find out how much graywater is produced in homes every day. They graph their results and discuss energy efficiency implications. Students are then challenged to find ways to reduce water use within the home.

Students learn about how engineers design and build shake tables to test the ability of buildings to withstand the various types of seismic waves generated by earthquakes. Just like engineers, students design and build shake tables to test their own model buildings made of toothpicks and mini marshmallows. Once students are satisfied with the performance of their buildings, they put them through a one-minute simulated earthquake challenge.

Students investigate the critical nature of foundations as they learn differences between shallow and deep foundations, including the concepts of bearing pressure and settlement. Using models representing a shallow foundation and a deep pile foundation, they test, see and feel the effects in a cardboard box test bed composed of layers of pebbles, soil and sand. They also make bearing pressure calculations and recommendations for which type of foundations to use in various engineering scenarios.

Students learn about STEM education through an engineering design challenge that focuses on improving building materials used in shantytowns. First, they consider the factors that lead to shantytown development. After researching the implications of living in shantytowns, students design, build and test cement-based concrete block composites made of discarded and/or recycled materials. The aim is to make a material that is resistant to degradation by chemicals or climate, can withstand natural disasters, and endure through human-made conditions (such as urban overcrowding or pollution). The composites must be made of materials that are inexpensive and readily available so that they are viable alternative in shantytown communities. Students assess the results both chemically and physically and then iterate their designs with the materials that proved to be strongest.

Students are introduced to brainstorming and the design process in problem solving as it relates to engineering. They perform an activity to develop and understand problem solving with an emphasis on learning from history. Using only paper, straws, tape and paper clips, they create structures that can support the weight of at least one textbook. In their first attempts to build the structures, they build whatever comes to mind. For the second trial, they examine examples of successful buildings from history and try again.

Students explore the basic physics behind walking, and the design and engineering of shoes to accommodate different gaits. They are introduced to pressure, force and impulse as they relate to shoes, walking and running. Students learn about the mechanics of walking, shoe design and common gait misalignments that often lead to injury.

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.

Students learn about the major factors that comprise the design and construction cost of a modern bridge. Before a bridge design is completed, engineers provide overall cost estimates for construction of the bridge. Students learn about the components that go into estimating the total cost, including expenses for site investigation, design, materials, equipment, labor and construction oversight, as well as the trade-off between a design and its cost.

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?

In this activity, students play the game Simon Says to make the amplitudes and wavelengths defined by the teacher. First they play alone, and then they play with a partner using a piece of rope.

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.

Students work with partners to create four different instruments to investigate the frequency of the sounds they make. Teams may choose to make a shoebox guitar, water-glass xylophone, straw panpipe or a soda bottle organ (or all four!). Conduct this activity in conjunction with Lesson 3 of the Sound and Light unit.

Through a five-lesson series with five activities, students are introduced to six simple machines inclined plane, wedge, screw, lever, pulley, wheel-and-axle as well as compound machines, which are combinations of two or more simple machines. Once students understand about work (work = force x distance), they become familiar with the machines' mechanical advantages, and see how they make work easier. Through an introduction to compound machines, students begin to think critically about machine inventions and their pervasive roles in our lives. After learning about Rube Goldberg contraptions absurd inventions that complete simple tasks in complicated ways they evaluate the importance and usefulness of the many machines around them. Through the hands-on activities, students draw designs for contraptions that could move a circus elephant into a rail car, create a construction site ramp design by measuring different inclined planes and calculating the ideal vs. actual mechanical advantage of each, compare the theoretical and actual mechanical advantages of different pulley systems conceived to save a whale, build and test grape catapults made with popsicle sticks and rubber bands, and follow the steps of the engineering design process to design and build Rube Goldberg machines.