Codemoji Coding Hour · Lesson plan
🔌 Light up circuits
Grades 2-8 · 60 minutes · No typing · Start at codemoji.com/lessons/maker
Students will
build circuits that work, and explain that power has to travel in a complete loop.
The big idea
Electricity only flows around a closed loop, from the battery and back again. A switch opens and closes the loop.
Before the hour
- Play missions 1-3 yourself (about 10 minutes).
- Decide on accounts: students can play as guests, or join your class with its code so their progress (and certificate) is saved.
- Optional: a real battery, bulb and two wires to show at the start.
Warm-up (away from screens)
Human circuit: students hold hands in a circle; one is the battery and squeezes a hand to "send power" around. Let go anywhere, and the power stops. That gap is an open circuit.
The hour
- 0-5 minWarm-up. The human circuit. Ask: what made the power stop?
- 5-10 minGet started. Open the mission map. Show how to wire: drag from dot to dot, or tap one dot then the other. Tap a wire to remove it.
- 10-45 minBuild. Missions 1-8, each helping one of the crew. Every step checks itself and says "Nice, that works!". Aim for mission 4 by minute 25.
- 45-55 minShow and share. Pairs explain one of their circuits: where does the power go?
- 55-60 minWrap-up. Certificates. Ask: where at home is there a switch that opens and closes a loop?
The lessons
- 1. Light Sully's tent
- 2. Pennyworth's night light
- 3. Ruby's doorbell
- 4. Acorn's fan
- 5. Deeno's party lights
- 6. Bamboo's two rooms
- 7. Bolts' battery trouble
- 8. Ruby's alarm
Where students get stuck
The light stays off
Follow the loop with a finger from + round to -. Find the gap.
The LED will not light
An LED only works one way round. Swap its two wires.
A warning about a short circuit
A wire goes straight from + to - with nothing in between. Remove it.
Talk about it
- Why did the light turn off when the loop had a gap?
- What does a switch really do?
- Why are short circuits dangerous in real life?
Fast finishers
- Level 2 in Gadget Grove: logic with two keys, dimmers and sensors.
- Draw a circuit for something in the classroom, like a doorbell for the door.
Words to know
- Circuit:
- A loop that electricity travels around.
- Switch:
- Opens or closes the loop to turn something off or on.
- Short circuit:
- Power taking a shortcut with nothing in its way. Not safe.
After the hour
Hand out Codemoji Coding Hour certificates: students who finished signed in to your class have theirs ready in your class's Certificates tab, and you can print any class by name. Standards: CSTA 1A-CS-02 / 1B-CS-02: how hardware and software work together; model a system.