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 provide a means of transferring electrical energy when heat, light, sound, and chemical changes are produced.

8 A SI 1: Abilities Necessary to do Scientific Inquiry: Grades 5-8

1.7 Communicate scientific procedures and explanations. With practice, students should become competent at communicating experimental methods, following instructions, describing observations, summarizing the results of other groups, and telling other students about investigations and explanations.

8 E ST 1: Abilities of Technological Design: Grades 5-8

1.2 Design a solution or product. Students should make and compare different proposals in the light of the criteria they have selected. They must consider constraints - such as cost, time, tradeoffs, and materials needed - and communicate ideas with drawings and simple models.

(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 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.