Kirchhoff's Current Law says the currents flowing into a node must add up to zero. Created by Willy McAllister.

This is an activity that demonstrates how batteries work using simple household materials. Learners use a pickle, aluminum foil and a pencil to create an electrical circuit that powers a buzzer. Most common batteries--such as car batteries and the batteries inside a flashlight--work on the same principle that the pickle battery works on: two metals suspended in an ion-rich liquid or paste separate an electric charge, creating an electrical current around a circuit. In this activity, the pickle provides the ion-rich liquid - pickles contain salt water, which is rich in ions.

Students make their own design decisions about controlling the LEDs in a light-up, e-textile circuit, plush toy project that they make using LilyPad ProtoSnap components and conductive thread. They follow step-by-step instructions to assemble a product while applying their own creativity to customize it. They first learn about the switches—an on/off switch and a button—exploring these two ways of controlling the flow of electric current to LEDs and showing them the difference between closed and open circuits. Then they craft their creative light-up plush pals made from sewn and stuffed felt pieces (template provided) that include sewn electric circuits. Through this sewable electronics project, students gain a familiarity with microcontrollers, circuits, switches and LEDs—everyday items in today’s world and the components used in so many engineered devices.

Students are introduced to circuits through a teacher demonstration using a set of Christmas lights. Then students groups build simple circuits using batteries, wires and light bulbs. They examine how electricity is conducted through a light bulb using a battery as a power source. Students also observe the differences between series and parallel circuits by building each type.

This lesson introduces the concept of electricity by asking students to imagine what their life would be like without electricity. Two main forms of electricity, static and current, are introduced. Students learn that electrons can move between atoms, leaving atoms in a charged state.

In this activity and demonstration about electricity and magnetism, learners observe how the current generated when one copper coil swings through a magnetic field starts a second coil swinging. Learners also explore what happens when they change the polarity of the magnet, reverse the coil, or add a clip lead to short-circuit the coils. Use this activity to illustrate how electricity and magnetism interact. The assembly of the electromagnetic swing device takes about an hour.

In this video, Jonathan travels to the Micronesian island of Yap in the middle of the Pacific to investigate large gatherings of the world's largest ray‰ŰÓthe manta. A research program there is tracking dozens of these animals and Jonathan learns what they're doing hanging around certain coral heads every morning. Please see the accompanying lesson plan on tides for educational objectives, discussion points and classroom activities.

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.

The application of engineering principles is explored in the creation of mobiles. As students create their own mobiles, they take into consideration the forces of gravity and convection air currents. They learn how an understanding of balancing forces is important in both art and engineering design.

In this activity about electricity and magnetism, learners examine what happens when a magnet exerts a force on a current-carrying wire. Using a simple device, learners discover that when an electrical current flows through a magnetic field, a force is exerted on the current and this force can be used to make an electric motor. Learners will experiment to find out what happens when they reverse the direction of current flow. They will also discover a mathematical tool called the "right-hand rule."

See how the equation form of Ohm's law relates to a simple circuit. Adjust the voltage and resistance, and see the current change according to Ohm's law. The sizes of the symbols in the equation change to match the circuit diagram.

See how the equation form of Ohm's law relates to a simple circuit. Adjust the voltage and resistance, and see the current change according to Ohm's law. The sizes of the symbols in the equation change to match the circuit diagram.

Students learn that charge movement through a circuit depends on the resistance and arrangement of the circuit components. In a hands-on activity, students build and investigate the characteristics of series circuits. In another activity, students design and build a flashlight.

In this activity, students learn about ocean currents and the difference between salt and fresh water. They use colored ice cubes to see how cold and warm water mix and how this mixing causes currents. Also, students learn how surface currents occur due to wind streams. Lastly, they learn how fresh water floats on top of salt water, the difference between water in the ocean and fresh water throughout the planet, and how engineers are involved in the design of ocean water systems for human use.

Students engage in an interactive "hot potato" demonstration to gain an appreciation for the flow of electrons through a circuit. Students role play the different parts of a simple circuit and send small items representing electrons (paper or candy pieces) through the circuit.

See how light knocks electrons off a metal target, and recreate the experiment that spawned the field of quantum mechanics.

See how light knocks electrons off a metal target, and recreate the experiment that spawned the field of quantum mechanics.

Students download the software needed to create Arduino programs and make sure their Arduino microcontrollers work correctly. Then, they connect an LED to the Arduino and type up and upload programs to the Arduino board to 1) make the LED blink on and off and 2) make the LED fade (brighten and then dim). Throughout, students reflect on what they've accomplished by answering questions and modifying the original programs and circuits in order to achieve new outcomes. A design challenge gives students a chance to demonstrate their understanding of actuators and Arduinos; they design a functioning system using an Arduino, at least three actuators and either a buzzer or toy motor. For their designs, students sketch, create and turn in a user's manual for the system (text description, commented program, detailed hardware diagram). Numerous worksheets and handouts are provided.

In this activity, learners construct a device out of a piezoelectric igniter, like those used as barbecue lighters. Learners use the device to remotely start current flowing in a simple series circuit containing a small electric fan.