Source: https://mokxi.com/teachers/plans/interactive-devices Updated: 2026-11-11 Lesson plan # Interactive devices on the Uno lesson plan Read people and sensors without blocking, control an output, then finish with two playable builds. 4 chapters, 9 lessons, about 8 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 - Wire a button correctly and turn a changing level into one deliberate action. - Measure elapsed time so one job never makes the board deaf to another. - Turn a changing voltage into a stable decision and a proportional output. - Use inputs, timing and feedback together in two projects you can play. ### Materials for the whole unit - Arduino Uno R3 - Buzzer - Full-size breadboard - LED x 2 - Piezo speaker - Pushbutton x 2 - Resistor x 4 - Slide switch 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 ## Read intent Wire a button correctly and turn a changing level into one deliberate action. Lesson | Time | What students do Reading a pin, and the pull-up A button with no resistor of its own, an input that must never float, and why pressed reads low. The single most common wiring in embedded work. | 55 min - Why pressed means low - Watch the pin go low - And the lamp follows - Check the pin rather than the lamp - Turn it upside down - The three wirings, and when to use each Press once for on, once for off The difference between a level and an edge, a variable that remembers, and the debounce window that makes a mechanical switch usable. | 55 min - A level is not an event - Run it - One press, one change - And the lamp agrees - And off again - What the debounce window costs ### Materials - Arduino Uno R3 - Full-size breadboard - LED - Pushbutton - Resistor ### Check for understanding Each student finishes "Press once for on, once for off" on their own, without opening the hints. The simulator checks 6 of its 6 steps as they go. Then ask each one to explain, in a sentence or two, the last thing it asked of them: "What the debounce window costs". Chapter 2. About 1 h 50 min ## Stay responsive Measure elapsed time so one job never makes the board deaf to another. Lesson | Time | What students do Two rates at once, without delay The pattern that unlocks everything else: keep when each thing last happened, and ask the time instead of waiting for it. | 55 min - Why delay cannot do this - Run it and count the red one - And the green one - Both lamps, both wired - Change one rate - Two details that are not optional Blinking and listening at the same time The payoff for non-blocking code: a board that keeps a rhythm and still answers a button in microseconds. Feel the difference by breaking it. | 55 min - One loop, two jobs - The blink keeps its rhythm - And the button still gets through - The second lamp follows your finger - Count five - Break it on purpose ### Materials - Arduino Uno R3 - Full-size breadboard - LED x 2 - Pushbutton - Resistor x 2 ### Check for understanding Each student finishes "Blinking and listening at the same time" on their own, without opening the hints. The simulator checks 6 of its 6 steps as they go. Then ask each one to explain, in a sentence or two, the last thing it asked of them: "Break it on purpose". Chapter 3. About 2 h 45 min ## Sense and act Turn a changing voltage into a stable decision and a proportional output. Lesson | Time | What students do Reading a voltage The ADC turns a voltage into a number from 0 to 1023. Build a divider, read two taps of it, and work out what a count is worth. | 55 min - What an ADC does - Read the top tap - And what it is in volts - Move the tap - Change the chain and predict the answer - What you would actually put there Deciding from a reading A lamp that fades up when the sensor says dark, and an indicator that does not. What a threshold is, why a ramp looks better than a jump, and where hysteresis comes in. | 55 min - The sensor, and what stands in for it - Run it, and make it dark - And the lamp comes up - Read the log - Let it go - The problem a threshold has Brightness from a digital pin Eight duty cycles on pin 9 next to a pin that can only be on or off. What PWM is, which pins have it, and what it is not good for. | 55 min - A pin has two states, so how is there a middle - Watch the steps - Full brightness - The pin with no timer - Make the sweep fast - What PWM is not for ### Materials - Arduino Uno R3 - Full-size breadboard - LED x 2 - Pushbutton - Resistor x 4 - Slide switch ### Check for understanding Each student finishes "Brightness from a digital pin" on their own, without opening the hints. The simulator checks 6 of its 6 steps as they go. Then ask each one to explain, in a sentence or two, the last thing it asked of them: "What PWM is not for". Chapter 4. About 1 h 50 min ## Finished builds Use inputs, timing and feedback together in two projects you can play. Lesson | Time | What students do Project: a reaction timer A lamp at a random moment, a button, and the milliseconds in between. Randomness, measuring time, and catching a cheat. | 55 min - The plan before the wiring - Run it and read the rules - Cheat, and get caught - Wait for the lamp - Take your time - Make it yours Project: a metronome A click on a piezo, a lamp on the beat, and two buttons that change the tempo without missing one. Making a note out of a pin. | 55 min - A note is a pin toggling - Run it and listen - A lamp on every beat - Speed it up - And slow it down - What the click costs, and what to add ### Materials - Arduino Uno R3 - Buzzer - Full-size breadboard - LED - Piezo speaker - Pushbutton x 2 - Resistor ### Check for understanding Each student finishes "Project: a metronome" on their own, without opening the hints. The simulator checks 6 of its 6 steps as they go. Then ask each one to explain, in a sentence or two, the last thing it asked of them: "What the click costs, and what to add". Your class ## Teach this unit as a class Start a class from this course and its 9 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. From gates to a computer 23 lessons, about 16 h. Build a claw machine 8 lessons, about 6 h. Build a vending machine 6 lessons, about 5 h. Every unit All the courses as ready-made units, on the teachers page.