The goal of this maker challenge is to demystify sensors, in particular the ambient light sensor, and to map its readings visually. In today’s world, we make sense of the environment around us by filling it with sensors, and we use output devices to display real-time data in a meaningful way. Take any smartphone as an example. Aside from the embedded camera and microphone, a number of other sensors collect a wide range of data. Depending upon the model, these sensors may collect data on proximity, motion, ambient light, moisture, compass, and touch. Some of these data are directly visualized through an app, while many operate internally and without a user interface, just below the surface of the screen. In order to become more familiar with the technology that we use (and often take for granted) on a daily basis, your challenge is to assemble a light sensor circuit, observe its readings using the Arduino Serial Monitor, and then create your own unique visualization by interfacing with the Processing software. Students learn how to use calibration and smoothing to capture a better picture of the data. Afterwards, they share their visualizations with the entire class. The time required for this challenge depends on students’ prior knowledge of Arduino and Processing software. Background resources for beginners help students get up to speed on microcontroller hardware and offer additional challenges for intermediate and advanced users.

Students apply sound-activated light-up EL wire to create personalized light-up clothing outfits. During the project, students become familiar with the components, code and logic to complete circuits and employ their imaginations to real-world applications of technology. Acting as if they are engineers, students are challenged to incorporate electroluminescent wire to regular clothing to make attention-getting safety clothing for joggers and cyclists. Luminescent EL wire stays cool, making it ideal to sew into wearable projects. They use the SparkFun sound detector and the EL sequencer circuit board to flash the EL wire to the rhythm of ambient sound, such as music, clapping, talking—or roadway traffic sounds! The combination of sensors, microcontrollers and EL wire enables a wide range of feedback and control options.

Graph theory is a visual way to represent relationships between objects. One of the simplest uses of graph theory is a family tree that shows how different people are related. Another application is social networks like Facebook, where a network of "friends" and their "friends" can be represented using graphs. Students learn and apply concepts and methods of graph theory to analyze data for different relationships such as friendships and physical proximity. They are asked about relationships between people and how those relationships can be illustrated. As part of the lesson, students are challenged to find the social graph of their friends. This prepares students for the associated activity during which they simulate and analyze the spread of disease using graph theory by assuming close proximity to an infected individual causes the disease to spread.

Based on their experience exploring the Mars rover Curiosity and learning about what engineers must go through to develop a vehicle like Curiosity, students create Android apps that can control LEGO MINDSTORMS(TM) NXT robots, simulating the difficulties the Curiosity rover could encounter. The activity goal is to teach students programming design and programming skills using MIT's App Inventor software as the vehicle for the learning. The (free to download) App Inventor program enables Android apps to be created using building blocks without having to actually know a programming language. At activity end, students are ready to apply what they learn to write other applications for Android devices.

Students learn about slope, determining slope, distance vs. time graphs through a motion-filled activity. Working in teams with calculators and CBL motion detectors, students attempt to match the provided graphs and equations with the output from the detector displayed on their calculators.

Students apply high school-level differential calculus and physics to the design of two-dimensional roller coasters in which the friction force is considered, as explained in the associated lesson. In a challenge the mirrors real-world engineering, the designed roller coaster paths must be made from at least five differentiable functions that are put together such that the resulting piecewise curving path is differentiable at all points. Once designed mathematically, teams build and test small-sized prototype models of the exact designs using foam pipe wrap insulation as the roller coaster track channel with marbles as the ride carts.

Students learn how to find the maximum power point (MPP) of a photovoltaic (PV) panel in order to optimize its efficiency at creating solar power. They also learn about real-world applications and technologies that use this technique, as well as Ohm's law and the power equation, which govern a PV panel's ability to produce power.

In this lesson, students will study how propellers and jet turbines generate thrust. This lesson focuses on Isaac Newton's 3rd Law of Motion, which states that for every action there is an equal and opposite reaction.

This lesson begins with a demonstration of the deflection of an electron beam. Students then review their knowledge of the cross product and the right hand rule with sample problems. After which, students study the magnetic force on a charged particle as compared to the electric force. The following lecture material covers the motion of a charged particle in a magnetic field with respect to the direction of the field. Finally, students apply these concepts to understand the magnetic force on a current carrying wire. Its associated activity allows students to further explore the force on a current carrying wire.

Students experience data collection, analysis and inquiry in this LEGO® MINDSTORMS® NXT -based activity. They measure the position of an oscillating platform using a ultrasonic sensor and perform statistical analysis to determine the mean, mode, median, percent difference and percent error for the collected data.

Students learn about the statistical analysis of measurements and error propagation, reviewing concepts of precision, accuracy and error types. This is done through calculations related to the concept of density. Students work in teams to each measure the dimensions and mass of five identical cubes, compile the measurements into small data sets, calculate statistics including the mean and standard deviation of these measurements, and use the mean values of the measurements to calculate density of the cubes. Then they use this calculated density to determine the mass of a new object made of the same material. This is done by measuring the appropriate dimensions of the new object, calculating its volume, and then calculating its mass using the density value. Next, the mass of the new object is measured by each student group and the standard deviation of the measurements is calculated. Finally, students determine the accuracy of the calculated mass by comparing it to the measured mass, determining whether the difference in the measurements is more or less than the standard deviation.

Students learn about sound waves and use them to measure distances between objects. They explore how engineers incorporate ultrasound waves into medical sonogram devices and ocean sonar equipment. Students learn about properties, sources and applications of three types of sound waves, known as the infra-, audible- and ultra-sound frequency ranges. They use ultrasound waves to measure distances and understand how ultrasonic sensors are engineered.

Students learn how volume, viscosity and slope are factors that affect the surface area that lava covers. Using clear transparency grids and liquid soap, students conduct experiments, make measurements and collect data. They also brainstorm possible solutions to lava flow problems as if they were geochemical engineers, and come to understand how the properties of lava are applicable to other liquids.

Students observe capillary action in glass tubes of varying sizes. Then they use the capillary action to calculate the surface tension in each tube. They find the average surface tensions and calculate the statistical errors.

Students calculate the viscosity of various household fluids by measuring the amount of time it takes marble or steel balls to fall given distances through the liquids. They experience what viscosity means, and also practice using algebra and unit conversions.

After conducting the associated activity, students are introduced to the material behavior of elastic solids. Engineering stress and strain are defined and their importance in designing devices and systems is explained. How engineers measure, calculate and interpret properties of elastic materials is addressed. Students calculate stress, strain and modulus of elasticity, and learn about the typical engineering stress-strain diagram (graph) of an elastic material.

Students explore the relationships between genetics, biodiversity, and evolution through a simple activity involving hypothetical wild mouse populations. First, students toss coins to determine what traits a set of mouse parents possesses, such as fur color, body size, heat tolerance, and running speed. Next they use coin tossing to determine the traits a mouse pup born to these parents possesses. These physical features are then compared to features that would be most adaptive in several different environmental conditions. Finally, students consider what would happen to the mouse offspring if those environmental conditions were to change: which mice would be most likely to survive and produce the next generation?

Students design systems that use microbes to break down a water pollutant (in this case, sugar). They explore how temperature affects the rate of pollutant decomposition.

Students obtain a basic understanding of microfluidic devices, how they are developed and their uses in the medical field. After conducting the associated activity, they watch a video clip and learn about flow rate and how this relates to the speed at which medicine takes effect in the body. What they learn contributes to their ongoing objective to answer the challenge question presented in lesson 1 of this unit. They conclude by solving flow rate problems provided on a worksheet.

After watching a short online video that recaps the enormous scale of accumulating plastic waste in our oceans, student teams are challenged to devise a method to remove the most plastic microbeads from a provided commercial personal care product—such as a facial cleanser or body wash. They brainstorm filtering methods ideas and design their own specific procedures that use teacher-provided supplies (coffee filters, funnels, plastic syringes, vinyl tubing, water, plastic bags) to extract the microplastics as efficiently as possible. The research and development student teams compare the final masses of their extracted microbeads to see which filter solutions worked best. Students suggest possible future improvements to their filter designs. A student worksheet is provided.