If / else with sensors — Electronics for kids

Remember

Test, then choose — “if the condition is true do the first part, otherwise the else part”

1. Put the reading into the condition: true → the if part, false → the else part.
2. > means strictly more and < strictly less; an equal reading makes them false.
3. AND: both true. OR: at least one true. In a chain, the first true condition wins.

Use it for: Programming sensors on a microcontroller board, automatic lights and fans, and coding logic lessons.

Worked example: 🤖 if (temperature > 30) { fan ON } else { fan OFF } The temperature sensor reads 32 °C. What happens? → fan ON

✏️ Practice

Work it out in your head or on paper, then tap your answer — or type it and press Check. Stuck? Press “Show me how”.

🏁 Lesson 24 test

20 questions. Check each answer, then go to the next one. Get 16 or more right to pass.

🏅 Sign in with Google to earn the 🔀 Sensor Decider badge when you pass — and a certificate when you finish all 10 lessons of Part 3 · Microcontrollers and IoT. You can still take the test without signing in.

🖨️ Electronics Worksheet: If Else with Sensors

• Worksheet set 1 (PDF)
• Worksheet set 2 (PDF)
• Worksheet set 3 (PDF)