Editor selections by Topic and Unit

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## Physical Sciences K-8:Electricity and Electrical Energy Units

Electricity is a natural phenomenon that can be both invisible AND visible, both matter and energy, a type of wave made of protons or a force that cannot be seen. It can move at the speed of light... yet it vibrates in a cord without flowing at all. It can be weightless, or have a small weight. Flowing in a light bulb filament, it transforms into light, but is not used up. It can  be stored in batteries. "Electricity" is not only a class of phenomena; it's a type of event.

### A Model for Electricity (2)

#### Activities:

This high-quality simulation, now in HTML5, can be easily adapted for both middle school and high school. Students build a virtual DC circuit by clicking & dragging  wires, batteries, switches, and resistors. This particular resource has received excellent reviews in extensive field testing, especially when done in conjunction with a hands-on lab.

Item Type: Interactive Simulation

What's the difference between voltage and current? And what does resistance have to do with anything? Many students, even after instruction, still need help to understand these basics. This activity features six molecular models to explore electron flow when voltage is applied to a wire, and when current flows in a circuit. We recommend only the first half for use in 8th grade physical science.

Item Type: Interactive Model
Duration: 1-2 Class Periods

### Electrical Charge (1)

#### Lesson Plans:

This lesson plan features the neon bulb, an object that can be lighted either by electric current or by static electricity.  Accompanied by detailed background information, this lesson promotes conceptual understanding of  electron transfer.

Item Type: Lesson Plan
Duration: One Class Period

### Moving Charges and Electric Circuits (6)

#### Lesson Plans:

This lesson was created specifically to go with the PhET DC Circuit simulator, and has received glowing reviews from teacher-users. It includes lesson plan, warm-up questions, and a detailed student guide on how to use the simulation. We highly recommend this as a way to let your students explore circuits, learn from mistakes, and be better prepared to participate in the hands-on circuit lab.

This module asks students to apply knowledge of electric circuits in designing a system where one switch can turn on multiple lights. Students work in teams to predict the difference between the two circuit designs, and then build examples of the two systems using wires, bulbs, and batteries. Editor's Note: We recommend teaming this lab with the PhET DC Circuit Simulator, found in "Activities" below.

Item Type: Lab Activity
Duration: Two Class Periods

#### Activities:

This high-quality simulation, recently rewritten to HTML5, is a good choice for introducing DC circuits. Students click and drag wires, batteries, switches, and resistors to explore factors that affect current, voltage, and resistance. The sim can be adapted for beginners or more advanced learners. This particular simulation has received excellent reviews in extensive field testing, especially when done in conjunction with a hands-on lab. See Lesson Plans above for recommended lessons developed by a high school teacher specifically for use with this simulation.

Item Type: Interactive Simulation
Duration: One Class Period

For the novice with little prior experience in circuit construction, this item offers well-organized step-by-step directions for building a simple circuit using a power pack system constructed by students. Also included is a tutorial on basic vocabularies needed to understand electricity.

Item Type: Activities
Duration: One Class Period

A collection of 8 experiments designed to introduce important concepts of electricity to beginning students. Each lab is accompanied by instructional tips to help students form a solid basis for a future study of resistance, Ohm's Law, and potential difference.

Item Type: Lab Experiments

#### Student Tutorials:

Good jumping-off point for students with little background in electricity. This is Chapter 1 of free online textbook, All About Circuits. With entertaining language and detailed diagrams, the author helps students form accurate concepts of electron transfer and charge interaction so they can successfully apply the knowledge in a lab.

Item Type: Online Tutorial

### Electric Force and Coulomb's Law (1)

#### Content Support For Teachers:

Middle school teachers may want to revisit Coulomb's Law before doing a unit on electricity. This interactive tutorial is very beneficial in explaining force as a vector quantity, how to determine the direction of electrical force vectors, and content support in calculations related to Coulomb's Law. It is part of The Physics Classroom collection.

#### Lesson Plans:

Want a seriously fun activity to introduce younger kids to electric circuits, but without the set-up hassle of circuit boards, resistors, leads, and switches? This innovative website, developed by an engineering professor, gives recipes for making circuits with homemade Play-Doh (one recipe for conducting dough; one for insulating dough). Other materials include LED's and a battery pack. HUGELY fun.

Item Type: Hands-On Activities
Duration: Multi-Day

#### Activities:

Middle school students need time to explore very simple circuits, if they are to build a foundation for future study of Ohm's Law, resistance, and potential difference. This set of 8 classroom experiments was designed to help them gain conceptual understanding by exploring simple circuits, diagnosing faulty circuits, and using voltmeters and ammeters.

This is a set of 5 creative labs on different types of batteries/electric cells. Two of them would be excellent choices for middle school. One lab replicates Alessandro Volta's historic experiments to construct the world's first electric battery: the voltaic pile. This experiment can be easily done in the classroom. The lemon cell is another good choice, using the acid from a lemon to increase conductivity between two metal strips.

#### References and Collections:

Want to brush up on the basics of electricity and circuits? This free web-based textbook is one of the best we've found that presents key ideas in the language of a non-physicist. Topics include electrostatics, conductors and insulators, simple and parallel circuits, resistance, voltage, and current. Highly recommended.

#### Student Tutorials:

This interactive Flash tutorial will give your students a good model for exploring electron flow through a simple circuit. It tackles a complex idea in a simple way, helping kids to build accurate concepts of what happens at the atomic level when current flows through a circuit.

### Applying Concepts of Electricity (4)

#### Lesson Plans:

A very effective lab for reinforcing the importance of circuit continuity. A lamp is connected to a battery with jumper wires. After measuring normal voltages in a functioning circuit, students break the circuit at each of the four connecting points, then measure again. Editor's Note: For additional practice in measuring voltage, see "Voltmeter Usage" activity below.

A collection of 8 experiments designed to introduce important concepts of electricity to beginning students. Each lab is accompanied by instructional tips to help students form a solid basis for a future study of resistance, Ohm's Law, and potential difference.

#### Activities:

A very good introduction to the multimeter, an electronic instrument that measures voltage, current, and resistance. It will help students become comfortable using either a digital or analog multimeter with batteries, an LED, and a simple "hobby" motor.

This is a companion lab to the resource directly above, "Voltmeter Usage". It helps students get practice in using the ammeter function of a multimeter to measure current -- the rate of electron flow in a circuit. Detailed instructions and photos make set-up easy.

### Electricity: A Historical Perspective (8)

#### Lesson Plans:

In this lab activity for Grades 5-9, students work in teams to construct a simple telegraph using a battery, wires, and a bulb. By turning the switch on and off, learners "send" messages using International Morse Code. Students then repeat the process sending identical messages on cell phones. Which group can send intelligible messages most quickly?  Editor's Note: This lab activity does not mimic the actual design of the original Morse device, which used electric current to move an electromagnet attached to the key device. Its purpose is to give a simple introduction to signal communications.

Item Type: Lesson Plan
Duration: One Class Period

#### Activities:

In this Java simulation, your students play with a replication of Coulomb's historic torsion balance: a device used to measure electric force between charges. Coulomb's methodical measuring laid the foundation for Coulomb's Law, a fundamental principle of electricity and magnetism.

It sometimes helps students with concept formation if they can see how early scientists made momentous discoveries. In this tutorial, students play with a simulation of the voltaic pile device invented in 1800 by Volta -- commonly known as the world's first battery. Battery cells can still be assembled using this "recipe". SEE ITEM DIRECTLY BELOW for a lab to construct the voltaic pile device in the classroom.

If you'd like your students to replicate Volta's groundbreaking experiment with the voltaic pile device (the world's first battery), here is a lesson plan (scroll down to Page 2 of the document). They will construct their own voltaic pile batteries and get a better understanding of how electrochemical reactions work. No harsh chemicals or safety hazards.

#### References and Collections:

In this excellent set of 50+ short biographies, kids can read about the challenges of early inventors AND follow links to simulations of the devices they invented. For example, the Coulomb biography offers a simulation of the torsion balance; the Volta biography has a simulated voltaic pile battery.

#### Student Tutorials:

In the 18th-century, Italian scientist Alessandro Volta proposed the theory that electrical current is generated by contact between different metals. His experimental work resulted in the "voltaic pile" battery, the first known source of sustainable electric current. For a simulation of the voltaic pile device, see "Activities" above.

This is a short biography of Charles Augustin de Coulomb, the 18th-century scientist whose experiments with a torsion balance gave rise to Coulomb's Law -- a fundamental principle of physics that defines the electrical force between two charged particles as a predictable mathematical relationship. For a simulation of Coulomb's torsion balance, see "Activities" above.

German physicist Georg Ohm was different, and his fellows at the time were not too supportive. This early giant in the field of electricity took a mathematical approach to electric current, at a time when his peers relied almost exclusively on lab experimentation. His perseverance resulted in Ohm's Law, which clarified the relationship between electrical current, resistance, and voltage. This is his biography.