Student teams creatively construct mobiles using hangers and assorted materials and objects while exploring the principles of balance and center of mass. They build complex, free-hanging structures by balancing pieces with different lengths, weights, shapes and sizes.

Whether you want to light up a front step or a bathroom, it helps to have a light come on automatically when darkness falls. For this maker challenge, students create their own night-lights using Arduino microcontrollers, photocells and (supplied) code to sense light levels and turn on/off LEDs as they specify. As they build, test, and control these night-lights, they learn about voltage divider circuits and then experience the fundamental power of microcontrollers—controlling outputs (LEDs) based on sensor (photocell) input readings and if/then/else commands. Then they are challenged to personalize (and complicate) their night-lights—such as by using delays to change the LED blinking rate to reflect the amount of ambient light, or use many LEDs and several if/else statements with ranges to create a light meter. The possibilities are unlimited!

Students build solar USB chargers using solar panels, rechargeable batteries, and other components.

Students construct bird nests and birdhouses. They research birds of their choosing and then design houses that meet the birds' specific needs. It works well to conduct this activity in conjunction with a grades 9-12 woodshop class by partnering the older students with the younger students (but it is not required to do this in order to conduct the activity).

In this hands-on activity, students explore the electrical force that takes place between two objects. Each student builds an electroscope and uses the device to draw conclusions about objects' charge intensity. Students also determine what factors influence electric force.

It is very dangerous to look directly at the Sun, even briefly. In this craft activity, you will create a safe viewer so you can look at the Sun without damaging your eyes.

Working as if they are engineers who work for (the hypothetical) Build-a-Toy Workshop company, students apply their imaginations and the engineering design process to design and build prototype toys with moving parts. They set up electric circuits using batteries, wire and motors. They create plans for project material expenses to meet a budget.

Students create their own anemometers instruments for measuring wind speed. They see how an anemometer measures wind speed by taking measurements at various school locations. They also learn about different types of anemometers, real-world applications, and how wind speed information helps engineers decide where to place wind turbines.

Students create models of objects of their choice, giving them skills and practice in techniques used by professionals. They make sketches as they build their objects. This activity facilitates a discussion on models and their usefulness.

Students build miniature model cities using sugar, bouillon and gelatin cubes. The cities are put through simulated earthquakes to see which cube structures withstand the shaking movements the best.

Student groups construct simple conductivity probes and then integrate them into two different circuits to test the probe behavior in solutions of varying conductivity (salt water, sugar water, distilled water, tap water). The activity culminates with student-designed experiments that utilize the constructed probes. The focus is to introduce students to the fabrication of the probe and expose them to two different ways to integrate the probe to obtain qualitative and quantitative measurements, while considering the application and utility of a conductivity probe within an engineering context. A provided handout guides teams through the process: background reading and questions; probe fabrication including soldering; probe testing and data gathering (including circuit creation on breadboard); probe connection to Arduino (including circuit creation and code entry) and a second round of testing and data gathering; design and conduct their own lab experiments that use the probes; online electrolyte/nonelectrolyte reading, short video, comprehension check and analysis questions.

Students are challenged to design their own small-sized prototype light sculptures to light up a hypothetical courtyard. To accomplish this, they use Arduino microcontrollers as the “brains” of the projects and control light displays composed of numerous (3+) light-emitting diodes (LEDs). With this challenge, students further their learning of Arduino fundamentals by exploring one important microcontroller capability—the control of external circuits. The Arduino microcontroller is a powerful yet easy-to-learn platform for learning computer programing and electronics. LEDs provide immediate visual success/failure feedback, and the unlimited variety of possible results are dazzling!

Students identify different bridge designs and construction materials used in modern day engineering. They work in construction teams to create paper bridges and spaghetti bridges based on existing bridge designs. Students progressively realize the importance of the structural elements in each bridge. They also measure vertical displacements under the center of the spaghetti bridge span when a load is applied. Vertical deflection is measured using a LEGO MINDSTORMS(TM) NXT intelligent brick and ultrasonic sensor. As they work, students experience tension and compression forces acting on structural elements of the two bridge prototypes. In conclusion, students discuss the material properties of paper and spaghetti and compare bridge designs with performance outcomes.

Students build their own small-scale model roller coasters using pipe insulation and marbles, and then analyze them using physics principles learned in the associated lesson. They examine conversions between kinetic and potential energy and frictional effects to design roller coasters that are completely driven by gravity. A class competition using different marbles types to represent different passenger loads determines the most innovative and successful roller coasters.

Working in teams of four, students build tetrahedral kites following specific instructions and using specific materials. They use the basic processes of manufacturing systems – cutting, shaping, forming, conditioning, assembling, joining, finishing, and quality control – to manufacture complete tetrahedral kites within a given time frame. Project evaluation takes into account team efficiency and the quality of the finished product.

Students investigate the weather from a systems approach, learning how individual parts of a system work together to create a final product. Students learn how a barometer works to measure the Earth's air pressure by building a model using simple materials. Students analyze the changes in barometer measurements over time and compare those to actual weather conditions. They learn how to use a barometer to understand air pressure and predict actual weather changes.

Students create and decorate their own spectrographs using simple materials and holographic diffraction gratings. A holographic diffraction grating acts like a prism, showing the visual components of light. After building the spectrographs, students observe the spectra of different light sources as homework.

This task is for instructional purposes only and builds on ``Building an explicit quadratic function.''

Students learn how to build simple piezoelectric generators to power LEDs. To do this, they incorporate into a circuit a piezoelectric element that converts movements they make (mechanical energy) into electrical energy, which is stored in a capacitor (short-term battery). Once enough energy is stored, they flip a switch to light up an LED. Students also learn how much (surprisingly little) energy can be converted using the current state of technology for piezoelectric materials.

This is the first of a series of task aiming at understanding the quadratic formula in a geometric way in terms of the graph of a quadratic function.