Switches control flow

Test switch outcomes, locate gaps and reason about changes.
What it is about
Predict the effect of opening/closing a switch.
Year 4 · 8–9 years · 30 challenges
Before you begin
- Lower KS2 enquiry, skeletons, light, materials and fair comparisons.
What the class will do
- Predict and experiment · 5 challenges
Predict and test switches
Use the fixed ideal two-switch series model. Lit tasks require a complete route; every open-switch arrangement is valid for a dark target.
- Match pairs · 7 challenges
Match states and gap locations
Pair each explicit configuration or transition with its unique contact/gap description. Several dark states are different configurations.
- Choose and explain · 18 challenges
Explain the changed route
Use each before/after record to predict the whole loop, preserve uncertainty and apply the classroom safety boundary.
Using it in class
Everyone predicts before a rotating representative acts. The fixed ideal series loop has one cell, bulb and two switches. Dark targets accept any open-switch state. Named configurations use text boards. No mains work. Full bank 35–45 minutes; discussion may take longer.
Give everyone time to think and discuss before one pupil acts at the board. The class explains and confirms together; hints and explanations stay until you move on.
Use an up-to-date browser on a computer connected to a whiteboard or shared display. Touch, mouse and keyboard; optional audio and reduced motion. No pupil accounts or personal devices.
Choose from 5 challenges up to the full activity. Discussion determines the duration: you set the pace.
Teacher Pro access includes all 30 challenges, interactive materials, hints and explanations for this activity.
A complete loop
Find the fault safely
Conductors and insulators