Item Description: Students may be in groups for this portion of the event. After each trial, record your observations in the data table. Before each of the following trials, separate the magnet and the galvanometer by several meters and orient the compass so its needle points due North.

Trials 1-3	Requires placing the north end of the magnet inside the tube.
Trial 1	Hold the magnet still with the tip just inside the tube.
Trial 2	Move the magnet slowly toward the tube; when the tip of the magnet is just inside the tube, stop. Then move the magnet slowly away from the tube and, when the magnet is two meters away from the tube, stop.
Trial 3	Move the magnet rapidly toward the tube; when the tip of the magnet is just inside the tube, stop. Then move the magnet rapidly away from the tube and, when the magnet is two meters away from the tube, stop.
Trials 4-6	Requires placing the south end of the magnet inside the same end of the tube as before.
Trial 4	Hold the magnet still with the tip just inside the tube.
Trial 5	Move the magnet slowly toward the tube; when the tip of the magnet is just inside the tube, stop. Then move the magnet away from the tube and stop, as in trial 2.
Trial 3	Move the magnet rapidly toward the tube; when the tip of the magnet is just inside the tube, stop. Then move the magnet rapidly away from the tube and stop, as in trial 2.

Students were asked the following question: Based on your results, describe the relationships between: (a) how fast you moved the magnet and the amount of current that flowed in the wire; and (b) the pole of the magnet (north or south) that was inside the tube and the direction of the compass' deflection.

Content Definition: When a coil of wire crosses a magnetic field it creates a current. The direction and strength of the current is indicated on the galvanometer. When the movement of the magnet is reversed the current is reversed. When the south pole of the magnet is inserted in the opposite end of the coil, the current is reversed. To increase the strength of the current, increase the movement of the magnet and/or increase the number of turns in the coil. The current can also be increased by using a stronger magnetic force. Electric current is generated by the movement of the coil in the magnetic field or the movement of the magnet in the coil. When both the coil and the magnet are stationary, no current is produced.

Mechanical energy, in the form of the hand moving the magnet into and out of the wire-wrapped tube, caused the magnet to cross the magnetic lines which creates a current.

Data Table

Trial	Pole of magnet inside tube (N or S)	Motion of magnet relative to tube (none, slow, fast)	Amount of deflection (degrees) as magnet moves:		Direction of deflection (E for east of north; W for west of north) as magnet moves:
			toward tube	away from tube	toward tube	away from tube
1	N	none	0-2 degrees	0-2 degrees	W
2	N	slow	0-5 degrees	0-5 degrees	W	E
3	N	fast	about 10 degrees	about 10 degrees	W	E
4	S	none	0-2 degrees	0-2 degrees	E
5	S	slow	0-5 degrees	0-5 degrees	E	W
6	S	fast	about 10 degrees	about 10 degrees	E	W

NOTE: Three important concepts in this exercise are:

• The amount of deflection is positively correlated to the speed of the magnet as it moves forward and away from the coil.
• The direction of deflection is changed by:
  • Changing the pole of the magnet induced into the coil.
  • The direction the magnet is moving, either toward or away from the coil.

Scoring Parameters:

• Based on data collected, the speed of the magnet's motion positively corresponds to the strength of the current (i.e., faster speed, more current).
• Based on data collected, changing the magnetic pole inserted into the coil reversed the direction of deflection.

Score Level Descriptions:

NS	Blank or irrelevant response is given.
1	Student response indicates minimal knowledge of the generation of electricity using a coil of wire and a magnetic field. Response says something about the magnet, current, and/or deflection of the compass. We put the north pole in and out of the tube six times.
2	Student response indicates some knowledge of the generation of electricity using a coil of wire and a magnetic field. The student discusses variation in speed of the magnet OR inserting the north or south pole of the magnet into the coil, however does not make connections between these aspects of the event and current generated and/or compass deflection.
3	Student response indicates an adequate understanding of the generation of electricity using a coil of wire and a magnetic field. The student communicates EITHER a positive relationship between speed of magnet movement and increase in current OR a change in pole used will reverse the direction the current is traveling.
4	Student response indicates a full understanding of the generation of current and its direction using a coil of wire and a magnet. Student communicates BOTH a positive relationship between speed of magnet movement and increase in current AND the change in the pole will reverse the direction the current is traveling.

Item Description: You live along a moving river, and you have lots of wire, a paddle wheel, and a huge bar magnet. Describe how you could use these materials to produce an electrical current. Include a diagram of your setup in your description.

Content Definition: When a coil of wire crosses a magnetic field it creates a current. Electrical current is generated by the movement of the coil in the magnetic field or the movement of the magnet in the coil. Mechanical energy, in the form of the moving water, can cause either the coil to cross the magnetic field to create a current.

Scoring Parameters:

• The student applies the materials given in the item (magnet, wire, and paddle wheel) to construct a generator.
• The student description uses mechanical energy from the river to move either the magnet or the coil of wire (in relation to a corresponding coil or magnet) to produce electricity.
• The student provides a diagram corresponding to the description.

Score Level Descriptions:

NS	Blank or irrelevant response is given.
1	The student response indicates a minimal understanding of the use of the materials to construct a generator. The response offers at least one strategy but is unable to relate it to the production of an electrical current. The diagram lacks one or more key components of a generator. I'd use the paddle wheel on the river and get an electrical current. I'd get energy from the water to make electricity.
2	The student response indicates some understanding of the use of the materials to construct a generator. The response uses or mentions each of the materials from the prompt but has an incomplete relationship between the materials and the production of an electrical current. The diagram is adequate but not complete. The paddle wheel turns in the water and the magnet has wire around it.
3	The student response indicates an adequate understanding applying the materials to construct a generator. The response describes how to use the materials to produce a current however one step in the process may be missing to make the model functional. The diagram is complete and accurate according to the description. The moving magnet within the coil of wire makes an electrical current.
4	The student response indicates a full understanding of the use of the materials to construct a generator. A full description includes a thorough and accurate discussion of how each material functions to make the working generator. A complete diagram is included. The paddle wheel turns the mechanical energy of moving water into electrical energy by moving the magnet within a coil of wire around the paddle wheel. When the coil of wire crosses the magnetic field, a current is created.