Introduction to activity: Below, we feature the published version of the example elicitation activity What happens with two bulbs?.
In this on-line sample activity, clicking on links to the “simulators” will open snapshots of the simulator setups in a separate window. The buttons and tools in these snapshots EXCEPT for the four buttons shown to the right (located on the lower right of the simulator image). Clicking on these four buttons allows you to switch between “realistic” and “schematic” views of the simulator, and to “turn on” or “turn off” the current simulation. Dimmed and depressed buttons are inactive.

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CE Activity II-E2: What Happens With Two Bulbs?

Name: Group: Class Period:

	Part I: Test your predictions
	Materials: two batteries in holders, three bulbs in sockets, wires.
	1. Use your electric-circuits kit to set up the circuits in Activity II-E1 and make the comparisons. To ensure fair comparisons, first check that the two batteries you use are each equally good at lighting a single bulb. Then set up the circuits and observe the relative brightness of the bulbs. Record your observations below by copying and pasting the appropriate label to the appropriate line.
	In recording your observations focus on large differences in brightness, rather than small differences that may occur if two of the "identical" bulbs are, in fact, not identical.
	Bulb B is	bulb A.	brighter than the same brightness as dimmer than out, so dimmer than
	Bulb C is	bulb A.
	Bulb C is	bulb B.
	Bulb D is	bulb A.
	Bulb E is	bulb A.
	Bulb E is	bulb D.
	Bulb D is	bulb B.
	2. To obtain feedback, open Act II-E2 Sim. First run the simulation in the Realistic mode. Then change to the Schematic mode and run the simulation again. Take a picture of the results and paste them on the next page. If any of the simulation results are not consistent with your observations, set up the circuits again and check your observations. (Discuss any persistent discrepancies with a staff member.) If necessary, change your observations above.
	3. (Do this individually.) If your predictions are not confirmed by what you observed, look back at your reasons for your predictions. Write "may need to change" next to those ideas that you wrote above about electricity that you now think may need to be changed in order to help you better understand the observations.
	Part II: Sense Making Discussion
	1. Listen to members of the class suggest ideas about the nature of electricity that might allow you to explain why two bulbs in Circuit II are the same brightness, and both are dimmer than a single bulb (in Circuit I). Record those ideas here.
	2. Listen to members of the class suggest ideas about the nature of electricity that might allow you to explain why two bulbs in Circuit III are the same brightness, and both are the same brightness as a single bulb (in Circuit I). Record those ideas here.
	3. Go to your group’s Idea Journal and enter your initial ideas for the following questions: Question #1: What effect do bulbs have on the flow of electricity in circuits? Question #2: How does adding bulbs to a circuits affect bulb brightness? Question #4: What is the nature of the flow of electricity in circuits?