Administration
Procedures
Description:
Students draw circuits and switches, explain how they work, then
change their design for someone without hands to turn the switch
on and off.
The task assesses students' abilities to follow simple instructions
to build a circuit, modify the design, and describe and diagram
the changes made.
This task is designed to take students approximately 20-30 minutes
to complete.
Overall Task Content Area:
- Physical Science
Specific Knowledge Areas:
- Electrical Circuits
Performance Expectations:
- using equipment
- apply scientific principles to develop explanations and solve
new problems.
National Science Education Standards:
8 B PS 3: Transfer of Energy: Grades 5-8
3.4 Electrical Circuits.
8 A SI 1: Abilities Necessary to do Scientific Inquiry:
Grades 5-8
1.2 Design and conduct a scientific investigation.
8 E ST 1: Abilities of Technological Design: Grades
5-8
1.2 Design a solution or product.
1.4 Evaluate technological designs or products.
(Use the "hot" link on the PALS
home page to check the full text of related National Science
Education Standards, if desired.)
General Teacher Instructions:
Students will be working in groups of 4 - 6 for the experiment/activity
part of this exercise. The following suggestions are offered to facilitate
administration of the exercise.
- Students need to be ready to work as soon as the period begins.
- Group assignments should be made in advance.
- The materials should be set out at each lab station, if possible.
- A central supply area, if needed, should be easily accessible.
- The supply area should have any supplies from the kit that
were prepared by the teacher as well as all of the school-supplied
materials necessary for the experiment.
- All the supplies should be clearly labeled.
Materials for "Electrical Circuits":
- 1 D-cell battery and battery holder
- 4 clip leads (wire with alligator clip)
- 1 bulb and socket
- 3 10-penny nails
- 2 straws
- 6 3" pieces of copper wire
- 6 3" pieces of aluminum wire
- 12" x 12" piece of aluminum foil
- 6 toothpicks per group
- 25 cm of string (kite string, fishing line, thread, thin twine)
per group
- 3 index cards per group
- 1 meter of masking tape
- 3 rubber bands per group
- 1 pen or pencil per student
Advanced Preparation:
- Cut 3" pieces of copper and aluminum wires for each group.
- Cut a 12" x 12" piece of aluminum foil per group.
- Cut 25 cm of string and 1 meter of masking tape for each group.
- Place materials at student work stations.
- Before you administer the exercise, test each bulb to make sure
that it lights.
Safety:
- Be careful.
- Teachers and students should always exercise appropriate safety
precautions and utilize appropriate laboratory safety procedures
and equipment when working on science performance tasks.
Task with Student Directions
Welcome to this experimental science test. We hope that you will
find it interesting and worthwhile. Carefully read through these
directions and the directions on the next page before you begin
to work.
You may be part of a group for the first part of this exercise.
Each group should carry out the experiment and collect the data
together, but each student must record the data in his or her own
booklet. Be sure to record the data exactly as you observe them.
After the data have been collected, each student should answer the
questions independently.
After you have finished your experiment and have recorded all
of the data, you will be asked to answer some questions about the
experiment and the data you recorded. Your answers must be written
in this test booklet in the space provided. Make sure that you understand
each question before you begin to write. At any time while you are
writing your answers, you may look back at the directions for the
experiment and the data you collected. Be sure that your answers
are written as clearly and neatly as possible.
Before you turn the page, read the list of materials
given below and check to make sure that your group has everything
listed.
Materials in the Kit
- 1 D-cell battery and battery holder
- 4 clip leads (wire with alligator clips at each end)
- 1 bulb and socket
- aluminum foil, 12 in x 12 in
- 6 pieces of aluminum wire
- 6 pieces of copper wire
- 2 straws
- 3 10-penny nails
Materials Supplied by the School
- masking tape
- 6 toothpicks
- 2 index cards
- 3 rubber bands
- 25 cm string
- pen or pencil
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Electric Switch
Your lab team has been hired to help remodel a house so people
who do not have the use of their hands will be able to turn the
lights on and off.
For the device to work you will need to:
- make a circuit that conducts electricity
- design a switch to turn the circuit on and off
- adapt your design for people who do not have the use of their
hands
Step 1. Make sure you can light a bulb.
Use the materials you have been given to create the circuit shown
in the diagram.
Figure 1
Does the light bulb light? If it does not, check to be sure that
you have constructed the circuit properly and ask your teacher to
make sure that your bulb and battery are working.
Step 2. Build a switch.
A switch is a device that can be used to connect
and break the circuit so that the bulb will turn off and on. Once
the bulb in your circuit lights, use the materials you have been
given to create a switch. Work with your switch until you can use
it to turn the light bulb on and off. Add the switch to the circuit.
Each member of the group should draw a diagram of the circuit
in his or her own booklet. In your drawing, you must show all parts
of the circuit and the switch. Each of the parts must be clearly
labeled. When you have finished your drawing, return to your
desk to finish Question 1 and work on Question 2.
Questions
Please answer the following questions by yourself.
1. Draw your circuit and switch. Explain how the switch
works.
2. Now figure out how you could change the design of the
switch so that a person without the use of his or her hands could
use it. Draw a diagram of your circuit showing the changes to the
circuit and switch that would allow a person to turn it off and
on without the use of hands. In your drawing, you must show all
parts of the circuit and the switch. Each of the parts must be
clearly labeled. Explain how this switch works.
Rubric
Item Description:
The following event deals with switches and how they can be modified
for persons who do not have the use of their hands. In the first question
students are asked to design (draw), and describe a simple circuit
and switch. Then, in the second question students are asked to design
and describe a modified switch. Answers to each may be found in either
question.
Before students work with switches, they first need a basic understanding
of what a simple circuit is and how to construct one. This is why
the first criterion (1) looks at whether or not students can at least
draw a circuit with a battery and a light bulb. To be considered complete,
a continuous path must lead from one end of the battery to the bulb
or bulb holder and back to the other end of the battery. Switches
are optional here but the circuit should look similar to Figure 1
in the student directions. Connections to the battery must be distinct.
Students are not asked to label anything in the first question but
if a circular path is not clear in any design, credit for a complete
circuit cannot be given.
The following three criteria focus on switches. Criterion 2 looks
simply for a circuit and switch that would effectively work to power
and control a light. Criterion 1 and 2 give a student two points for
a working circuit and switch. Some students may provide a short circuiting
switch which is basically a wire that when hooked up, bypasses the
light and turns it off. Again, labeling is not a factor as long as
the paths are clear and the only intentional break is at the switch.
How students design a switch, for someone who does not have the use
of the hands, is the main focus in this event. Criterion 3 looks at
the design itself. Here, students must label the switch as such or
at least label the main parts of it to show a clear switch design.
If no labeling of the switch is provided, no credit can be given.
If the switch is labeled and the design could be controlled without
the use of hands, then credit should be given. A switch that calls
for the rolling up of aluminum foil with the feet or fastening an
alligator clip by mouth, may seem impossible, but are challenges disabled
people face everyday. The student's design is limited to the materials
listed in the student directions.
Finally, criterion 4 looks at the student's description of how their
switch works. The student must address the use of some other body
part like the elbow, foot, or mouth and how the part operates the
switch. The student may receive credit here if there is no drawing
but rather a clear description of how a person would operate the switch.
The Item:
Question #1: Draw your circuit and switch. Explain how the switch
works.
Question #2: Now figure out how you could change the design of the
switch so that a person without the use of his or her hands could
use it. Draw a diagram of your circuit showing the changes to the
circuit and switch that would allow a person to turn it off and on
without the use of hands. In your drawing, you must show all parts
of the circuit and the switch. Each of the parts must be clearly
labeled. Explain how this switch works.
MAIN CONCEPTS
- A complete circuit is one in which you can start at one end
of the battery and follow the circuit path around to the light
bulb or light bulb holder and back to the other end of the battery.
Normally, the only break in a complete circuit is at the switch.
- A complete working circuit with a switch clearly shows all of
the circuit component connections and its design shows that it
would effectively power and control the light.
- Students should be able to draw and label their modified switch
idea. A clear design requires little, if any, explanation. The
modifications should allow a person, without the use of his or
her hands, to control the light.
- Students should be able to describe how their modified switch
works. How a disabled person actually controls the light without
their hands is important to designing a modified switch. Drawings
can not always clearly show alterations in how a modified switch
is intended to be used.
Scoring Rubric Summary
Criterion 1: |
1) Provides a complete circuit. |
Criterion 2: |
1) Provides a complete working circuit and switch.
OR
2) Provides a complete working circuit and modified switch.
OR
3) Provides a complete working circuit and short circuiting
switch. |
Criterion 3: |
1) Clear drawing of modified switch. (Switch
or main parts must be labeled!) |
Criterion 4: |
1) Clear description of how modified switch works. |
Electrical Circuits and Switches Rubric
(The following criteria may be met in either question one or question
two.)
(Descriptions can be helpful in clarifying parts of the circuit and
switch drawings that are not clearly labeled.)
Criterion 1: |
1) Provides a complete circuit (switch is optional
here), that clearly shows a circular path from one end of
the battery to the bulb or bulb holder and back to the opposite
end of the battery. Switch, if included, is the only place
a break in the circuit may appear. |
Criterion 2: |
1) Provides a complete circuit with a simple
hand operated switch, that would effectively work to power
and control the light.
OR
2) Provides a complete circuit with a modified (no hands)
switch, that would effectively work to power and control
the light.
OR
3) Provides a complete circuit with a short circuiting switch
that would effectively work to power and control the
light. |
Criterion 3: |
1) Provides a switch design that could
be operated by a person who did not have the use of their
hands. The switch or its main parts must be labeled to receive
a point. |
Criterion 4: |
1) Provides a clear description of how
a person operates the switch without their hands. One example
might call for a person to use their mouth to disconnect a
clip lead. |
Technical
Quality Information
These data were prepared by American College Testing (ACT) based
on a field test of this Performance Event.
Unit Name: |
Electrical Circuits |
Unit Content: |
Physical Science |
Unit Theme: |
Acquiring Information and Constructing Meaning |
|
Unit Statistics:
Event Score |
0 |
1 |
2 |
3 |
4 |
N |
5.00 |
22.00 |
32.00 |
41.00 |
20.00 |
N |
Mean |
Standard Deviation |
Standard Error |
120.00 |
2.41 |
1.10 |
0.10 |
|
Examples
of Student Work
There are two examples for each score point ranging from 4 to 0.
Explanations of the scores were written by staff from American College
Testing (ACT) who conducted training and scoring of field tested
events.
Event Score = 4
|