The Making Room

The Smart Sensor Lab: Build a Smart Plant Monitor

A 3-hour hands-on lab for ages 6–12. Kids build and code a sensor that checks when a plant needs water — the “brain” of a self-watering plant.

When
Saturday, 31 October 2026
9:15am–12:30pm
Where
River Valley, Singapore — exact location by email
Who
Ages 6–12, each with one adult
Group size
15 families at most
Book a place→
S$68S$78per family (1 adult + 1 child) · founding family price for our first run
A micro:bit wired to a soil moisture sensor in a potted plant
The morning

What if screen time could become making time?

In one morning, your child builds a smart plant monitor: a small device that checks the soil and tells you when a plant needs water. It is the same idea behind real smart-farming systems.

Along the way they wire a soil moisture sensor to a micro:bit, code it in MakeCode, and test it on a seedling they pot themselves. To finish, our trainer shows the whole self-watering plant in action — and how they can build it next on Makers Online.

One kit each, not one shared between four

No watching over someone’s shoulder. Every child wires, codes and runs their own micro:bit V2 for the whole session.

Real hardware, real data

Kids code a micro:bit V2 and a soil moisture sensor in MakeCode blocks, read live readings from real soil, and see their code answer back on the board.

Parents are part of it

Watch your child’s first program light up, learn the basics yourself in a short Parent Primer, then build together in the Parent-Child Build and cheer them on at the Showcase.

The code goes home with them

Kits stay with us, but the code they write stays on their laptop. They can keep going at home on Makers Online — in the MakeCode simulator, no kit needed — or with a kit of their own.

What they learn

From switching it on to a working monitor.

  • Physical computing: connect code to a micro:bit V2 and a soil moisture sensor
  • Sensors: how a soil moisture sensor tells wet soil from dry, and turns it into a number
  • Coding: MakeCode blocks that read the sensor and respond to what it reads
  • Testing: try it on real soil, watch what changes, and adjust the code until it works
  • Safe hardware habits: which pins never touch, and why water and electronics stay apart
Pick a mission

In the build, each child picks a level on Makers and works through its steps with their grown-up, the same way building at home works. Same hardware, three levels — so a 6-year-old and a 12-year-old both finish with something that works.

  1. 1
    Plant Whisperer

    Show a happy or sad face for wet or dry soil.

  2. 2
    Plant Doctor

    Show a moisture bar graph and play a sound when the soil is dry.

  3. 3
    Plant Engineer

    Add the micro:bit’s light or temperature sensor to make a “plant mood” — or both, for kids who want the extra challenge.

Schedule

Three hours, three ways to be in the room.

Some parts are for everyone, one hour is kids-only, and the build is done together. During the kids-only hour you can join the Parent Primer, or step out and be back by 11:05.

  1. 9:15–9:30

    Arrival & setup

    Together
    • Check in, pick up name tags, meet the facilitators and the other families
    • Laptops on the Wi-Fi, Chrome open, logged in to Makers
    • One coffee or non-coffee drink each from the drinks vendor
  2. 9:30–9:45

    Welcome & today’s mission

    Together
    • Meet the Code Gakko team and see what Makers is
    • The mission: build a Smart Plant Monitor
    • A quick icebreaker with the family next to you
  3. 9:45–9:55

    Why water matters

    Together
    • Water and sustainability, close to home
    • The question for the morning: how can we water a plant only when it needs it?
  4. 9:55–10:05

    Kit handout & safety

    Together
    • Each child gets a numbered micro:bit V2 kit, soil moisture sensor and wires, on loan for the session
    • A short safety briefing: no water on the board, and which pins must never be joined
  5. 10:05–10:35

    Micro:bit essentials

    Kids-only
    • The micro:bit and the MakeCode editor
    • Upload a first program to the board

    Parents: Stay and watch the first program light up (10:05–10:20), then a hands-on Parent Primer over a drink: the sensor in wet and dry soil, what your child is learning, and how to help without taking over.

  6. 10:35–11:05

    Sensor wiring lab

    Kids-only
    • Power, ground and signal pins
    • Wire the soil moisture sensor to the micro:bit
    • How the sensor tells wet soil from dry

    Parents: Free time over a drink, and decorate a pot for your child’s seedling. You can step out — please be back by 11:05.

  7. 11:05–11:25

    Drinks & pastries

    Everyone
    • Pastries for everyone and a drink for the kids
    • Facilitators catch up anyone who needs a hand; everyone else sketches their dream smart garden
  8. 11:25–12:05

    Parent-Child Build: Smart Plant Monitor

    Together
    • Pot a herb seedling in the pot you decorated
    • Open the build on Makers and pick a mission level (below) — each level is a set of steps to follow together, with facilitators going round to help
    • Code the monitor to read and show live soil moisture, then react to “wet” and “dry”
    • Test it on mystery soil and on the seedling
  9. 12:05–12:30

    Showcase, next steps & graduation

    Together
    • Gallery walk: every child presents their monitor and tries out others
    • Demo: the monitor driving a servo, then a water pump — the full self-watering plant
    • How to carry on with Makers Online, and the kit options
    • Certificates and a group photo
What they leave with

Something growing, something working, and a way to keep going.

Kits are on loan for the morning, so there’s nothing to buy or bring. Everything below goes home with you.

Their own potted seedling

The herb they potted and tested their monitor on, with a card saying how often it needs water.

Their code

Kept on their own laptop, ready to open and change at home.

A Makers Guide

The coding and hardware ideas from the morning on one page, plus safety tips for building at home.

A certificate and an e-badge

A printed certificate on the day, and an “IRL Event” badge on their Makers profile.

S$10 off Makers Online

Credit towards their first month, for families who want to keep building.

A free 3D-printed micro:bit case

A protective case for the micro:bit, free if you buy a kit on the day: Essentials Kit (S$39) or Starter Kit (S$65, with a Makers subscription).

After the morning

The first build is the hardest one to start alone.

That’s what the morning is for. Your child goes home having already wired a sensor and made it work, and you go home knowing what the next step looks like.

Book a place

Saturday, 31 October

1 adult + 1 childS$78S$68
Each extra child (own kit and seat)+S$50

Founding family price: this is our first run, so every family who joins it pays S$68 instead of S$78.

Please bring

  • A personal laptop with Chrome and a USB-C port (or a USB-C adapter)
  • The laptop charger
  • School-issued laptops often block the micro:bit connection, so please bring a personal one if you can

Places aren’t refundable, but they’re never lost. If you can’t make it, use the link in your confirmation email: until 28 October you can pass your place to a friend who can come, and after that it becomes credit for a future Making Room session (valid for 12 months). If Code Gakko ever has to cancel a session, every family is refunded in full.

Already on Makers? Use the email linked to your account, so your child’s badge lands on their profile. New to Makers? We’ll set up a free account for you.

Children coming
TotalS$681 adult + 1 child

Secure payment through HitPay. Your place is held for 30 minutes while you pay. Have Making Room credit? Use the same email and it comes off at checkout.

Questions

Good to know.

None. The morning starts from switching the micro:bit on. Mission levels let younger and older kids go as far as suits them, and older kids who finish early get extension challenges.

Yes, with their grown-up close by. Ages 6 to 8 usually need more help with wiring and reading the screen, which is why every child comes with an adult and the main build is done together.

Please stay for the first and last parts. During the kids-only hour (10:05–11:05) you can join the Parent Primer, decorate your child’s plant pot, or step out — just be back by 11:05 for the build together and stay until 12:30.

Yes. Book them together: each extra child is S$50 and gets their own kit and table space. One adult can look after up to three children.

Yes. Book with the email linked to your Makers account and your child will use their own login on the day, so the code and the badge land on their existing profile.

We set up a free Makers account for you straight away and email the login. Before the day, log in and add your child — it takes a couple of minutes, and it means their work is saved from the first upload.

Kits are on loan for the session. The code stays on your laptop and runs in the MakeCode simulator at home, no kit needed. If they want to keep building with hardware, you can buy an Essentials Kit (S$39) or Starter Kit (S$65) on the day and take it home, with a free 3D-printed protective case for the micro:bit.

Each place is prepared for a particular child — a numbered kit, a printed certificate, a seedling and a seat at a table — and in a room of 15 families there is usually someone waiting for it. So we ask families to book only when they’re sure, and we don’t take cancellations or give refunds. Plans do change, though, so a place is never wasted: pass it to a friend up to 3 days before, or keep it as credit for another session, and we offer the seat to the next family on the waiting list.

Book with the same email address and it comes off the price automatically at checkout. If it covers the whole place, there’s nothing to pay.

There are pastries and drinks. Tell us about any allergies when you book and we’ll plan around them.

Yes, we take photos of the room and the builds. You can tell us when you book if you’d rather your child isn’t in any we share.

Places aren’t refundable, but they’re never lost. If you can’t make it, use the link in your confirmation email: until 28 October you can pass your place to a friend who can come, and after that it becomes credit for a future Making Room session (valid for 12 months). If Code Gakko ever has to cancel a session, every family is refunded in full.

Yes. When a family can’t come and keeps their place as credit, we email the next family on the list and hold the place for them for 24 hours (12 hours in the last three days). If they don’t take it, it goes to the next family.