Source: https://mokxi.com/teachers/plans/christmas-lights Updated: 2026-11-11 Lesson plan # Build Christmas lights lesson plan Four holiday builds on the Uno, from a star on the tree to a light show synced to a song, each one ready to hang up. 2 chapters, 4 lessons, about 4 hours, on the Arduino Uno R3. Every lesson runs in the browser, with nothing to install. Start a class from this course The unit ## Objectives and materials ### By the end, students can - Light a star on one data wire and ring real bells from a doorbell. - Count down to Christmas from a real-time clock, then sync three strips to a song. ### Materials for the whole unit - Addressable RGB LEDs x 3 - Arduino Uno R3 - DFPlayer Mini MP3 module - Eight-digit display, MAX7219 - Full-size breadboard - Half breadboard - Hobby servo - Pushbutton - Real-time clock, DS3231 - Resistor x 4 - Speaker, 8 ohm Every part is already on the simulator’s bench, so there is nothing to buy or hand out. The counts are the most any one lesson uses, if you build it on real breadboards too. Chapter 1. About 1 h 50 min ## The tree and the door Light a star on one data wire and ring real bells from a doorbell. Lesson | Time | What students do Build 1: a tree topper star A ring of 16 WS2812B LEDs behind a star cutout, with four shows a button steps through. How one data wire drives every LED, and how to draw a frame without delay(). | 55 min - Run it: the star lights - Next show - One frame at a time - On the tree Build 2: a sleigh-bell doorbell Press the doorbell and a servo shakes real sleigh bells while a speaker plays Jingle Bells. A tune as two arrays, tone(), and a servo that keeps the beat. | 55 min - Run it - Ring it - One press, one chorus - On the porch ### Materials - Addressable RGB LEDs - Arduino Uno R3 - Half breadboard - Hobby servo - Pushbutton - Resistor - Speaker, 8 ohm ### Check for understanding Each student finishes "Build 2: a sleigh-bell doorbell" on their own, without opening the hints. The simulator checks 4 of its 4 steps as they go. Then ask each one to explain, in a sentence or two, the last thing it asked of them: "On the porch". Chapter 2. About 2 h 5 min ## The window and the roof Count down to Christmas from a real-time clock, then sync three strips to a song. Lesson | Time | What students do Build 3: a countdown in the window A DS3231 keeps the date and an eight-digit MAX7219 display counts down to Christmas morning. Why a real-time clock beats millis(), and date arithmetic with DateTime. | 55 min - Run it: days to go - Why a real-time clock - The display - Christmas Day Build 4: a light show synced to music A DFPlayer plays the song and three LED strips follow a cue list timed in beats. How synced shows really work, what xLights does at a larger scale, and what this sketch does by hand. | 70 min - How synced light shows work - Run it: the song starts - The cue list - Three strips, one clock - The end of the song ### Materials - Addressable RGB LEDs x 3 - Arduino Uno R3 - DFPlayer Mini MP3 module - Eight-digit display, MAX7219 - Full-size breadboard - Half breadboard - Real-time clock, DS3231 - Resistor x 4 - Speaker, 8 ohm ### Check for understanding Each student finishes "Build 4: a light show synced to music" on their own, without opening the hints. The simulator checks 5 of its 5 steps as they go. Then ask each one to explain, in a sentence or two, the last thing it asked of them: "The end of the song". Your class ## Teach this unit as a class Start a class from this course and its 4 lessons are assigned in one go, in order. Students join with a six-character code or printed login cards, and each one’s work comes back to you. The class tools are free for 30 days for one class of up to 20 students, with no card. The lessons themselves are free either way. Start a class from this course See the demo class More units ## Other lesson plans Electronics basics 20 lessons, about 10 h. Embedded on the Arduino Uno 16 lessons, about 12 h. Embedded on the ESP32-C3 13 lessons, about 11 h. Embedded on the Raspberry Pi Pico 7 lessons, about 6 h. Build your own fight stick 5 lessons, about 4 h. Embedded on the STM32F411 6 lessons, about 6 h. C++ on a board 13 lessons, about 10 h. Digital logic and memory 4 lessons, about 4 h. Interactive devices on the Uno 9 lessons, about 8 h. From gates to a computer 23 lessons, about 16 h. Build a claw machine 8 lessons, about 6 h. Every unit All the courses as ready-made units, on the teachers page.