Science
Strand IV
Use Scientific Knowledge from the Physical Sciences in Real-World Contexts

 

Science/Strand IV
Content Standard 1
All students will measure and describe the things around us; explain what the world around us is made of; identify and describe forms of energy; and explain how electricity and magnetism interact with matter (Matter and Energy)

 

Science/Strand IV/Content Standard 1
Middle School

 

Science/Strand IV/Content Standard 1/Middle School
Benchmark 5
Construct simple circuits and explain how they work in terms of the flow of current.

Benchmark Clarification

Electrical energy is the flow of electrons from one place to another. Energy is transferred when an electron moves from one atom to another. The energy is transferred through a conductor or material such as air, a copper wire, a human body, etc. Electricity will follow the path of least resistance through a material. Materials that will not conduct electricity are called non-conductors.

In order for this movement to occur, the path or circuit must be closed and complete, which allows the energy to flow back to the original power source.

An open circuit is not a complete circuit because of a break in the pathway.

A short circuit is a complete, but unintended flow of energy that will take the easiest pathway back to its starting place. A short circuit may not always be the shortest path. Short circuits are often caused by insulated wires that become worn, which causes contact between the two wires. Fires may begin in homes due to short circuits.

Students will:

  • Describe electricity as an energy transfer from a power source (such as a battery) through a conductor (such as a wire) to an electrical device (such as a bulb) and then back to the power source.

Key Concept / Real World Context / Instructional Example / Assessment Example / Resources

 

Science/Strand IV/Content Standard 1/Middle School/Benchmark 5
Key Concept

  • complete circuit
  • short circuit
  • conductors
  • non-conductors

Tools:

  • batteries
  • household current
  • bulbs
  • bells
  • motors
  • electrical switches

 

Science/Strand IV/Content Standard 1/Middle School/Benchmark 5
Real World Context

  • household wiring
  • electrical conductivity testing
  • electric appliances

 

Science/Strand IV/Content Standard 1/Middle School/Benchmark 5
Instructional Example

Benchmark Question: How does current flow in simple circuits?

Focus Question: How many ways can you find to light a light bulb?

The teacher will give groups of students a “C” or “D” cell battery, a flashlight bulb, and two pieces of wire. Ask students to see if they can make the bulb light. Students will find several ways to make the bulb light. Students will discuss similarities among the different ways they found to light the bulb. For example, the points of contact on the battery will always remain the same.

Next, the students will try to light the bulb using one wire. As students experiment, explain that an electric bulb lights when it is part of a continuous path of materials that form a loop through which the electrical current moves. This path/ loop is called a circuit. Students will draw the circuit in each arrangement they make and label the current flow with arrows.

(Extension: Discuss various examples of simple circuits used in manufacturing, transportation, energy distribution, and housing.)

Constructing: (SCI.I.1.MS.1), (SCI.I.1.MS.2), (SCI.I.1.MS.3).

Reflecting: (SCI.II.1.MS.2), (SCI.II.1.MS.4).

 

Science/Strand IV/Content Standard 1/Middle School/Benchmark 5
Assessment Example

After several completed activities on circuits, students will use the following materials to create at least four complete circuits that light a bulb and/or activate a buzzer: batteries, wires, light bulbs, switches, buzzers, and various conducting and non-conducting materials (e.g., paperclips, paper fasteners, tin foil, straws, etc.).

(Give students rubric before activity.)

Scoring Rubric

Criteria

Apprentice

Basic

Meets

Exceeds

Correctness of circuits

Constructs fewer than two correct simple circuits.

Constructs two to three correct simple circuits.

Constructs and completes four correct simple circuits.

Constructs and explains four correct simple circuits.

Completeness of diagram

Completes fewer than two correct diagrams.

Completes two to three correct diagrams.

Completes four correct diagrams.

Completes four correct diagrams, gives correct explanations of electron flow, and may give explanations and diagrams of failed attempts.

 

Science/Strand IV/Content Standard 1/Middle School/Benchmark 5
Resources

Webliography.
http://mtn.merit.edu/mcf/SCI.IV.1.MS.5.html

Electrical Connections. AIMS.
http://wwws.aimsedu.org/aimscatalog/default.tpl

Electrical Current/Light & Optics. Bill Nye Video. Disney Educational (800/295-5010).

Electricity. TOPS.
http://topscience.org/