Course outline

From one light to a device they designed themselves.

The whole course is one idea, repeated and widened: something senses, code decides, something acts. By week 4 a student can say that sentence about their own build. Every week after swaps one part of it for something more interesting.

Everything is water

One analogy, used consistently for eight weeks. It makes even the failures predictable — a balloon inflated backwards bursts, and so does a capacitor.

   VOLTAGE   is water PRESSURE
   CURRENT   is FLOW RATE          (cm³ per second)
   RESISTOR  is a THIN TUBE
   CAPACITOR is a BALLOON          (fills, empties — and bursts if reversed)
   DIODE     is a ONE-WAY VALVE
   GROUND    is the RESERVOIR      everything returns to

Week by week

Every session ends with something that works. That's the rule the course is built around.

Week	What they build	What they learn
1	An LED and a button, on a board they keep	What voltage, current and resistance are — in water. Why an LED only works one way round
2	A light that fades by itself	Capacitors as balloons that fill and empty. Diodes as valves — and what happens when you force one backwards
3	A blinking light, under software control	First Python. What a microcontroller actually is: a tap you can program
4 ⭐	A dial that mixes any colour	Analog in, analog out. Press the dial to switch between brightness and colour modes
5 ⭐	An eight-note synthesizer	Eight buttons, one octave. What sound is — and that pitch is just switching speed
6	A light sensor and a moisture sensor	That every sensor does the same three things: read a number, decide, act
7 ⭐	A plant monitor that works	Building to a specification, then calibrating it against three real plants
8	Their own device, demonstrated to parents	Designing something nobody specified — then explaining what went wrong and how they fixed it

The code is real

Short enough to type, real enough to matter. This is the whole of week 4 — the dial controls the brightness.

from machine import ADC, Pin, PWM
from time import sleep

dial = ADC(Pin(26))
led  = PWM(Pin(15))

while True:
    led.duty_u16(dial.read_u16())
    sleep(0.01)

One line does the work: the number coming off the dial becomes the brightness of the light. Students who understand that line understand what every sensor in the world is doing. Week 6 is the same program with the dial swapped for a moisture probe — which is exactly the point.