How this works
Nothing here needs an account, and nothing here costs anything. If your question is not below, write to us and a person will answer.
Starting from nothing
You do not need an account. Say how old the learner is and start, or open any topic in the catalog and read it. Progress saves in that browser, so closing the tab does not lose it.
The first few questions are wider than the ones after them. They are working out where the learner already is, so the answers matter more than the score, and a run of wrong answers early is normal rather than bad news.
What an account adds
An account is free and takes an email and a password. It keeps progress across devices, lets one adult follow more than one learner, and opens the family view, where you can see what is moving and what is fading.
If you started without one, you can keep what you have: sign up from the same browser and the sky you built comes with you.
What a session is
Short. A handful of questions, each one chosen from what the learner has shown so far: something due for review, something they have never been asked, or a check on the topic underneath the one that just went wrong.
Every question shows its working afterwards, right or wrong, because the explanation is the part worth reading. Nothing is timed and nothing is marked in red. A single wrong answer is checked with a second question before it changes anything, because one bad answer on a bad day proves very little.
Reading the sky
Every topic is a star. Lit means learned, glowing means nearly there, and a cool grey star is one the learner has not met yet.
Brightness says how fresh the learning is. A star dims slowly after it is lit, because memory does that, but a learned star never goes dark: it settles to a warm amber instead. When it has dimmed far enough, that topic comes back in a session.
Seeing where a learner is
Each subject has a level, and each subject page has a track showing where the learner is standing, what is behind them, and what comes next. Two numbers appear on the same page and mean different things: stars lit counts what has been proven, while the track counts everything behind them, including what was assumed from their age.
Nothing is assumed forever. An assumed topic is checked the first time it matters, and it drops back if the check goes badly.
Following more than one learner
The family view lists the learners on your account, with what each one is working on. You can add a learner there, and give another adult access to a learner without handing over your account: a tutor or a grandparent gets their own sign-in and sees only the learners you shared.
Stardust and the sky shop
Answering earns Stardust, a little at a time, and only from questions the app chose. It buys things to place in the learner's own sky: a comet, a crescent moon, a satellite. Nothing costs money and nothing can be bought with it that changes the learning.
Themes
A learner can pick a world: hockey, soccer, dinosaurs, space, ocean or magic. It changes the drawings, the sky, and the flavour of the questions the app generates. The written lessons stay exactly as they are, so a theme is decoration and motivation, not a different curriculum.
Away from the screen
Any topic page can print a worksheet: A4, questions on the front, and an answer page for grown-ups to fold away before handing the rest over. No screen and no internet needed once it is printed.
Adding your own topics
A pack is a set of topics you write yourself, with lessons and questions, wired into the same prerequisite graph as everything else. Keep it private, share it with another adult by email, or export it as a file and hand it to someone.
Ready-made packs cover things schools rarely teach. Switch one on for a learner and it joins their sessions like any other subject.
Why any of it matters
Every career in the explorer is mapped to the school topics it is actually built on, so "why do I need this" has an answer with a path in it. Open a job to see what it leans on, or open a topic to see which jobs lean on it.
Something looks wrong
If a lesson is confusing, an answer looks wrong, or a topic is in the wrong place, tell us. Every lesson page has a report link at the bottom, which is the fastest way: it carries the page with it, so we know what you were looking at. Content mistakes usually get fixed the same week.
What we keep
We keep what is needed to remember progress, nothing is sold, and a child is never shown an advert. The privacy page says exactly what is stored and what your choices are.
Developers and AI assistants
The catalog is open to machines as well as people: a public API, the whole library as plain text, and a Markdown twin of every public page. Ask the catalog a question in plain words and it answers with the topics that cover it.
Still stuck
Tell us what you were trying to do and what happened instead. Every message is read by a person, and the reply comes from one. If it is a mistake in a lesson, the report link at the bottom of that lesson page is faster: it carries the page with it, so we know exactly what you were looking at.