Spark & Anvil is built to reach kids where the internet doesn't. You can download the entire portfolio — every game, story, and book — as a single self-contained package, carry it on a USB stick or an external drive, and use it with no internet at all. In places with limited or intermittent internet, the networked features (like playing with a friend across devices) turn on automatically whenever a connection is available.
It's the same free, on-device, no-accounts, no-tracking experience — just complete on arrival. Built for classrooms, libraries, rural and remote homes, and any lab that runs air-gapped.
Nothing else ever leaves the device — no account, no sign-in, no analytics. A bundle never phones home.
The library comes in two editions — the same free, signed, on-device experience; they differ only by a small set of topic games. Pick the one that fits where it's going.
The full library minus a small set of civic / news / history topics.
The default. A clean-travelling edition for settings where some of those topics are sensitive. Same games, stories, and books everywhere else.
Every game, story, and book — the complete portfolio.
Best for most homes, schools, and libraries with open access to the full curriculum.
The two editions differ by a handful of civic, news, and history games only — everything else (all math, science, reading, arts, logic, and SEL games, plus every story and book) is identical in both.
PDF books are the bulk of the weight, so the library comes in tiers — take just what you need. Each is one download; the big number is the download (.zip) size, which unzips to a larger folder.
Library as of August 17, 2026 (version 2026.08.17). New content ships continuously; a bundle is a point-in-time snapshot, and its live features (playing with a friend, community picks) stay current whenever you're connected.
The whole site and every game, fully playable. The USB-stick starter.
1.7 GB download · unzips to ~3 GB
Everything in Lite, plus every narrated, illustrated story and audio drama.
10 GB download · unzips to ~12 GB
The entire library, nothing left out — for an external drive or an air-gapped lab.
31 GB download · unzips to ~34 GB
Need just one thing? We can build a custom slice — a single subject (e.g. just Math), a single app, or a single age band — so it fits a smaller stick. Email hello@sparkanvil.org with what you'd like.
Unzip the bundle, then start the tiny local server that ships inside it — that's all. (Opening
index.html directly won't work; a modern site needs a real
http:// address, which the little server provides.)
Double-click serve.command Double-click serve.bat Run ./serve.sh Run python3 serve.py
Then open http://localhost:8080 in any browser. A
START_HERE.txt inside the bundle repeats these steps.
A tablet can't run the little server itself, so run it on one computer (or a Raspberry Pi / spare laptop) on the same Wi-Fi, then browse to it from your tablets — the same way offline-classroom tools like Kolibri and RACHEL work.
Tablets on this Wi-Fi: http://192.168.1.42:8080/. Good to know: over the tablet's Wi-Fi
address the "Add to Home Screen" / offline install won't switch on (a browser security rule that
applies to everything except localhost) — but everything else works fully, because
the server is right there on the network. A standalone on-tablet app is a planned follow-on.
Networked "Play together" (room-code multiplayer) keeps working with no internet at all, as long as both players are on the same Wi-Fi network (a home router, or one device's hotspot). The little server that ships with the bundle carries a built-in room relay, so it hosts the game for everyone on the network — the same server that already serves the library.
http://192.168.…:8080/ address for the Wi-Fi.Good to know: everyone must be on one Wi-Fi network (it won't reach across separate networks or the internet). Same-device pass-and-play always works with no network at all. As always there is no chat and no voice — only game moves and a small set of preset emotes, rooms are code-gated, names are made up on the spot, and nothing is stored — the lowest-data way to play together.
Every bundle ships tamper-evidence so you can confirm it's the real, unmodified Spark & Anvil library — even with no internet, and even after it's been copied to a USB stick and passed around.
Inside the bundle, run python3 verify.py. It re-checks every
file against the built-in list and reports OK or tampered. No install, no internet.
With the free minisign tool:
minisign -Vm MANIFEST.sha256 -P RWRF5eP/YgRuOyXP3LhQfNTjqgsJ0px0W0MN/hJcrhYlPGi6CJBgIFPn
Our signing public key is RWRF5eP/YgRuOyXP3LhQfNTjqgsJ0px0W0MN/hJcrhYlPGi6CJBgIFPn —
always verify against this copy on our HTTPS site (channel separation), not one bundled elsewhere.
This is tamper-evident, not tamper-proof: these materials are free (CC BY-NC-SA) and you're welcome to copy or adapt them — but our signature can't be forged, so you can always tell a genuine Spark & Anvil bundle from a modified one.
Every bundle is the same free, on-device experience: no ads, no in-app purchases, no accounts, no tracking, and nothing leaves the device. Read our privacy commitment.
Building a computer lab, library, or classroom around this? Email hello@sparkanvil.org — we're glad to help.
Make reading comfier. Saved on this device only — nothing leaves your device.