Learn / Circuits / Base / Your first circuit: one light, one switch
BASE
BEGINNER
Ages 8+
3:40
Your first circuit: one light, one switch
One battery, one LED, one switch. The whole idea of a circuit — a loop the current can travel — in about two minutes of building.
VIDEO · exercise walkthrough · chapters: parts · build · test · why
Blocks you need
Battery · LED · Switch · 2 wires
You'll understand
What a circuit isOpen vs closedPolarity marksWhy the loop matters
Steps
1Connect the battery block to a wire on each side.
2Snap the LED across the two wires — polarity marks facing the same way.
3Put the switch into the line on one side of the battery.
4Flip the switch. Light on, light off — you've opened and closed the loop.