In this lesson, students will first review how to make colorful lights with an RGB LED using regular resistors. Then, they’ll build a new project: a motion-activated LED using a PIR detector (a sensor that detects movement).

Paintbox RGB LED Recap

We’ll start by revisiting the RGB LED project, this time using regular resistors instead of potentiometers.

In Tinkercad, students will:

• Place an RGB LED on the breadboard.
• Connect each color pin (red, green, blue) through a resistor.
• Mix colors by changing which legs are connected.

This exercise helps reinforce resistor use and reminds students how color mixing works with LEDs.

New Project: Motion Activated LED

Next, we’ll introduce a brand-new component: the PIR (Passive Infrared) sensor.

Students will learn that:

• PIR sensors detect heat and movement, like when a person walks by.
• They’re used in automatic lights, security systems, and even some toys.

In Tinkercad, we’ll connect the PIR sensor to an LED circuit:

• When motion is detected, the LED turns on.
• When no motion is detected, the LED turns off.

This shows how sensors bring circuits to life, letting them respond to the environment.

PIR sensor

An example of PIR sensor application

Wrap-Up

By the end of this session, students will:

• Refresh their understanding of RGB LEDs and resistors.
• Build their first motion-activated project using a PIR sensor.
• See how electronics can be both colorful and interactive.

Also, I would throw in a safety video here for education: