This page provides the directions and questions as they were presented to students who took the Electrical Circuits task. In addition, following each question is a sample response, the scoring criteria used to judge performance on the question, and performance data for students in the nation.

In this task, students learn to assemble a simple electrical circuit. Then, students design and conduct an investigation to compare the conductivities of different materials. Finally, students use their knowledge learned from comparing circuits having one or two light bulbs to design and conduct an investigation to determine which of two black boxes contains a light bulb.

See the test booklet.

# PART 3

You will now investigate if adding a second bulb to the circuit shown in Diagram 4 will affect the brightness of the bulbs.

Diagram 4 (reprinted below from page 6) shows a circuit with one bulb (Bulb 1). Diagram 6 on the next page shows a circuit that includes a battery and two light bulbs in a row (Bulb 1 and Bulb 2).

# Question 6

Now set up a circuit like the one shown in Diagram 6 (with Bulb 1 and Bulb 2). Remember that you may need to look straight down from the top to see Bulb 1 and Bulb 2 clearly.

What did you observe about the brightness of Bulb 1 using two bulbs in your circuit compared to the brightness of Bulb 1 using one bulb in the circuit?

Sample correct student response:

Explain what you think was happening in the circuit.

Sample correct student response:

# Question 6: Scoring Guide

Score and Description

Complete:
Student response provides a correct explanation that consists of two parts:

• Indicates that Bulb 1 was less bright (dimmer) when using two bulbs in the circuit compared to the brightness of Bulb 1 when using one bulb in the circuit.

• Indicates that there is less (little) current flowing through two bulbs than one bulb.

Partial:
Student response addresses one part of a correct explanation.

Unsatisfactory/Incorrect:
Student response is inadequate or incorrect.

Percentage of fourth-grade students in each response category: 2009
Complete Partial Unsatisfactory/ incorrect Omitted
24 36 38 1
NOTE: Detail may not sum to totals because of rounding.

SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2009 Science Assessment.