STE
Buddy
🐾
Voice
On
The Codex Society
Music
For ages 8–12

Turn What ifs into Experiments

Real science projects, wrapped in story dispatches kids want to open.
We Don't Just Teach Science.
We Train Junior Scientists.
AI can hand your child an answer in seconds. STEMBuddy teaches the harder skill: how to investigate, reason from evidence, and explain what they found.
THINKINGASSISTANTWhy is the sky blue?Sunlight scatters off the air,and blue scatters the most.
The answer lands. The thinking doesn't.
Ask AI “Why is the sky blue?” and a correct answer arrives in seconds — but it never becomes theirs. Your kid has the fact, yet never ran the test, weighed the evidence, or explained why.
BEYOND QUICKANSWERSINTO QUESTIONS,TESTS & REASONING
THE STEMBUDDY WAY
Big wonder, smaller steps
STEMBuddy gives your kid the same question and a way to answer it: you can’t test the whole sky, so they build a tiny one in a glass — change one thing, watch what happens, and explain it — with coaching that keeps their voice, never a pasted answer. The conclusion is one they proved, and can defend.
See how the shift works in practice
ONE INVESTIGATION, START TO FINISH
Here's exactly what your kid does.
Not flashcards, not a quiz. A real science investigation — they ask, test, and explain, the same loop real scientists use.
My InvestigationsPLANTS & NATURECan light change howtall a plant grows?⚡ 40%2/4 stepsNext adventure:Make a PredictionKeep Going!Played 2h agoWhy does warm waterdissolve sugar faster?
1
Pick a real question
Your kid chooses something they actually wonder about — like “Can light change how tall a plant grows?”
HypothesisMake your predictionIFI give the plant more lightTHENit will grow tallerBECAUSEplants use light to maketheir own foodCoachNice start — can you say why?You write it. The coach only nudges.Next: run the test →
2
Make a guess, then test it
They predict what will happen, then run a fair test for real and record what they see — even when it’s not what they guessed; in science, that’s the win. Coached, never written for.
FIELD REPORTFILED JUN 8REAL-WORLD TESTPrediction supportedMore light made theplants grow taller.Predicted it, tested it, backed it with their data.THINKING PRACTICEDFair Test DesignNGSS · SEP-3Evidence → ReasoningNGSS · SEP-7THE RESULTS82h134h186h218h4 trials · taller with more light (cm)WHAT IT MEANSPlants turn light into food, so morehours of light gave them more to grow with.FILED
3
Explain what they found
They finish with a Field Report — a signed record of what they tested, what they found, and why. No points for lucky guesses.
An AI coach guides every step with hints, structure, and safety nudges. It never hands over the answer.
REAL PROJECTS, REAL REASONING
Kids start with a question. STEMBuddy helps them turn it into a fair test.
They choose a project, make a prediction, collect evidence, and explain what they found — with AI guidance that supports the work without doing it for them.
The 5-step Investigation
Where your kid runs a real experiment — hypothesis to conclusion.
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Codex Society dispatch
Story-driven dispatches that pull your kid back three nights in a row.
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Claim-Evidence-Reasoning
Where your kid practices defending a conclusion with evidence — the form of every serious argument.
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Show your work
Every investigation ends in a Field Report — a signed record of what your kid tested, what they found, and why.
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Topics are the vehicle. Reasoning is the skill.
REAL EXPERIMENTS INSIDE
Kid-tested projects: safety first, then fair tests and clear thinking.
Investigation ideas inspired by real student science fairs worldwide and active citizen science programs. New projects added every week across seven science categories.
Can a Bigger Parachute Slow It Down?
Motion & Forces
Can a Bigger Parachute Slow It Down?
Why Warm Water Wins the Race
Chemistry
Why Warm Water Wins the Race
Can Light Change Plant Height?
Plants & Nature
Can Light Change Plant Height?
Paper Bridge Shape Battle
Engineering
Paper Bridge Shape Battle
Can You Build a Real Rain Gauge?
Earth & Weather
Can You Build a Real Rain Gauge?
Where Do Worms Choose to Go?
Animals
Where Do Worms Choose to Go?
Does a Recycling Guide Reduce Mistakes?
Science
Does a Recycling Guide Reduce Mistakes?
Can a Bigger Parachute Slow It Down?
Motion & Forces
Can a Bigger Parachute Slow It Down?
Why Warm Water Wins the Race
Chemistry
Why Warm Water Wins the Race
Can Light Change Plant Height?
Plants & Nature
Can Light Change Plant Height?
Paper Bridge Shape Battle
Engineering
Paper Bridge Shape Battle
Can You Build a Real Rain Gauge?
Earth & Weather
Can You Build a Real Rain Gauge?
Where Do Worms Choose to Go?
Animals
Where Do Worms Choose to Go?
Does a Recycling Guide Reduce Mistakes?
Science
Does a Recycling Guide Reduce Mistakes?
How High Can a Ramp Send It?
Motion & Forces
How High Can a Ramp Send It?
Can Salt Put Mold Growth on Hold?
Plants & Nature
Can Salt Put Mold Growth on Hold?
Bridge Battle: Beam, Arch, or Truss?
Engineering
Bridge Battle: Beam, Arch, or Truss?
Why Salt Makes Ice Vanish Faster
Chemistry
Why Salt Makes Ice Vanish Faster
After the Rain, What Dries First?
Earth & Weather
After the Rain, What Dries First?
Nature's Hidden Pattern Code
Animals
Nature's Hidden Pattern Code
Spring Sprout Speed Test
Plants & Nature
Spring Sprout Speed Test
How High Can a Ramp Send It?
Motion & Forces
How High Can a Ramp Send It?
Can Salt Put Mold Growth on Hold?
Plants & Nature
Can Salt Put Mold Growth on Hold?
Bridge Battle: Beam, Arch, or Truss?
Engineering
Bridge Battle: Beam, Arch, or Truss?
Why Salt Makes Ice Vanish Faster
Chemistry
Why Salt Makes Ice Vanish Faster
After the Rain, What Dries First?
Earth & Weather
After the Rain, What Dries First?
Nature's Hidden Pattern Code
Animals
Nature's Hidden Pattern Code
Spring Sprout Speed Test
Plants & Nature
Spring Sprout Speed Test
ABOUT THE STORY WORLD

The Codex Society.

The bells are ringing again.
The Codex Society is a long line of scientists and researchers who never accept an answer they haven't tested. Its founders — the Elder Seven — were to their world what Newton, da Vinci, and Marie Curie are to ours.
For generations, the Society has preserved tested truth in the Codex. Now the Static is returning: the pressure to accept fast answers, skip evidence, and stop thinking carefully.
So the Society is calling new Junior Investigators.
Inside STEMBuddy, that calling becomes real science work: your child receives dispatches, tests their own ideas, collects evidence, and files Field Reports with their Field Companion.
The science is real. The story gives kids a reason to come back.
No spoilers: the first cases are earned inside the app.
PARENT TRUST
Four rules we will not bend with your child’s work.
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Parents guide. Kids investigate.
You can suggest questions and send briefings, but your child writes the hypothesis, tests the idea, and explains the result.
How parent briefings work →
AI supports the work. It does not do the thinking.
STEMBuddy helps with structure, prompts, and next steps — but the final claim, evidence, and reasoning belong to your child.
How AI scaffolding works →
No public kid feed. No comments. No social pressure.
STEMBuddy is not a children’s social network. Kids build investigations, not profiles for strangers.
How we handle safety →
Published work is reviewed first.
A Field Report only becomes a Codex Entry after review. No auto-publish, no open posting.
How Codex review works →
Built for parents who want their kids to practice reasoning, not just collect answers. STEMBuddy uses story to create momentum, but the outcome is serious: a child who can ask better questions, test ideas, and explain what they found.
— Min, founder
Free to start — no credit card. When they're ready for more, paid plans start at $8.25/mo, billed annually.
See full pricing →