Science
Circuit lab: series and parallel
Switch between a series circuit and a parallel circuit, adjust the number of cells and toggle each of three bulbs. The diagram shows current and voltage values, while a prediction question asks what happens to the other bulbs when one is removed from a parallel circuit.
Series: one shared circuit path. Open the activity to compare it with parallel branches.
Read the complete materialRead the material
Switch between a series circuit and a parallel circuit, adjust the number of cells and toggle each of three bulbs. The diagram shows current and voltage values, while a prediction question asks what happens to the other bulbs when one is removed from a parallel circuit.
Circuit lab: series and parallel. Use the preview for diagrams and layout.
Choose Series or Parallel, set one to four cells and toggle bulbs A, B or C. The diagram and table report the modelled current and voltage. In series, an open bulb breaks the shared loop. In parallel, each bulb has a separate branch. A final question asks pupils to predict the effect of removing one bulb.
A teaching sequence
Compare how a break in one bulb’s path affects a series circuit and a parallel circuit, using the model diagram and readouts to support an explanation.
Series: one shared circuit path. Open the activity to compare it with parallel branches.
Read the complete materialTrace the series loop
Choose Series and trace the single route through bulbs A, B and C. Record the current and voltage values the diagram displays.
Is there one complete path or several?
Predict an open bulb
Click a bulb to open it. Observe the path, readouts and remaining bulbs, then explain why the current changes in this model.
What happened to every bulb when the shared loop was broken?
Compare parallel branches
Switch to Parallel and restore the bulbs. Open one branch and compare what happens in the other branches.
Which branches remain complete when one bulb is opened?
Explain the model's result
Answer the question about removing a bulb from a parallel circuit. Ask pupils to link their choice to the independent paths shown in the diagram.
How do the independent paths explain the bulbs that stay lit?
Before you teach
Look for the thinking behind an answer, choose the support your class needs and leave room for an independent response.
What to look for
Look for a distinction between one shared path and separate branches. A pupil might say, “In parallel, the other bulbs stay lit because they still have a complete branch.” Ask: “What would change if the break were in the main path before the branches?”
Give a little support
Trace each path in a different colour on a printed or projected copy of the screen. Begin by following one bulb within the three-bulb diagram in one mode, then trace the other bulbs and compare their paths. Provide the terms branch, complete path and break as a small word bank.
Take the idea further
Ask pupils to predict what happens to the displayed current when the cell count changes in each mode. Have them explain which readings belong to a branch and which describe the whole circuit, then compare the explanation with a circuit diagram.
Things to keep in mind
This is an idealised circuit model. It assumes identical bulbs and fixed cell voltages, and omits real wire resistance, battery condition and component variation. The displayed values are calculated examples, not measurements from equipment. Follow normal electrical safety rules for any physical investigation.
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Ideas to try with your class
Sample teaching perspectives on what to try, what to adapt and what to watch for.
Meet The Creators
Meet a creator whose teaching interests connect with this template.
Open Book Pause
This Year 8 interactive model switches between series and parallel circuits, changes the cell count and lets pupils open bulbs A, B or C while viewing current and voltage readouts. A question asks what happens to other bulbs when one parallel bulb is removed.
Helpful Highlighter
The one-loop series path can be compared with separate parallel branches. Predicting first, then opening one bulb and tracing the remaining paths connects the readout to the model's structure.
Extra Page
Trace each path in a different colour and begin with two cells and one bulb change. Use branch, complete path and break as a small word bank before explaining why unbroken parallel bulbs stay lit in this model.
Book and Biscuit
The activity is an idealised calculated model with identical bulbs and fixed cell voltages; its values are not measurements. It omits wire resistance and real battery variation, so pair it with a teacher explanation and normal electrical safety practice.