Unscanned
Turn a typed worksheet into one small practice file that every learner can open: with a screen reader, a keyboard, large text, offline, on an old phone.
Built during AccessED Hacks, October 17 to November 20, 2026 (all code written from October 24, 2026). No pre-existing code.
Who it is for
The learner: a middle-school student who is blind or has low vision and uses a screen reader (for example TalkBack on an Android phone). Their class worksheets arrive the way many worksheets travel today: a phone photo or a scanned PDF posted in the class chat group. To a screen reader, a photo of a worksheet is a single "image". There is no question to read, no option to choose and no way to know whether an answer is right. The learner waits for someone to read it to them, or skips it.
The teacher: has the worksheet already, usually as a document they typed. They do not have time to learn accessibility rules or a new platform, and many of their learners share old phones with little or no data.
The barrier removed: the worksheet exists, but not in a form the learner's device can read or interact with. Unscanned turns the teacher's text into a file that can be read, navigated and answered without sight, without a mouse and without internet, and that gives the teacher's own feedback after each answer.
What it does
Teacher side (the web app):
- Paste or type the worksheet in a forgiving plain-text format (below), or start from an example.
- The checker lists problems as you type ("Question 3 has options but none is marked correct") and shows a live, working preview.
- Press Download practice file. You get one
.html file of about 22 to 25 KB. Send it by WhatsApp, Bluetooth, email or USB stick.
Learner side (the generated file):
- Real structure for screen readers: a page heading, one heading per question, multiple-choice options grouped and named by their question, typed answers labelled by their question.
- Every action works from the keyboard (Tab, arrows, Space, Enter), with a thick visible focus outline.
- Instant feedback in a polite live region ("Not quite. You chose 2/6. Try again, or open the hint."), then the teacher's worked explanation. Learners can retry as often as they like. Open questions show the teacher's model answer after the learner writes their own.
- Reading options: text size up to 200%, three alternative colour schemes (light on black, high-contrast black on white, dark on cream), and wider letter, word and line spacing (the WCAG 1.4.12 values).
- Optional read-aloud buttons using the device's own speech engine (
speechSynthesis), shown only when the browser has it.
- Progress and settings are saved on the device (
localStorage), with a visible note if the browser blocks saving. "Clear my answers" lets the next learner on a shared phone start fresh.
- No network at all: the file carries a Content-Security-Policy of
default-src 'none', so it cannot load or send anything. It works the same opened from a USB stick with the phone in airplane mode.
- With JavaScript switched off (some chat apps' built-in viewers), the text, options and explanations are still readable.
The worksheet format
One thing per line, blank line between questions.
Title: Adding fractions with different denominators
About: Maths, Grade 6
Instructions: Answer each question, then press Check answer.
Language: en
# Part 1
Q: What is 1/2 + 1/4?
a) 2/6
b) 3/4 *
c) 2/4
Hint: Change 1/2 into quarters first.
Explain: 1/2 is the same as 2/4. Then 2/4 + 1/4 = 3/4.
Q: Write 6/8 in its simplest form.
Answer: 3/4 | three quarters
Explain: Divide the top and bottom by 2.
Q: Why is 1/2 + 1/3 not 2/5?
Model answer: You cannot add the bottoms...
Q:, Question: or 1. start a question. Options can be a), (a), -, [ ] / [x]. Mark the right one with a trailing *, (correct), a tick, or [x]. Two or more marked options make a "choose all that apply" question.Answer: makes a typed-answer question; separate accepted answers with |. Capitals, extra spaces, curly quotes and a final full stop are ignored. Nothing else is guessed (so 6/8 is not accepted for "simplest form of 6/8" unless you list it).Hint:, Explain: and Model answer: are optional. Any other line is reading text. # Heading starts a section.Language: sets the file's language code so screen readers and read-aloud pick the right voice.
Run it locally
Nothing to install for the app itself. Open index.html in a browser, or serve the folder:
node tests/server.js # serves http://127.0.0.1:4173/
Tests (Node 18+):
npm install
npx playwright install chromium
npm test # rebuilds examples/, runs every test, writes tests/RESULTS.md
LIVE_URL=https://bowen1314.github.io/unscanned/ npm run test:live # smoke test of the live site
How it works
src/unscanned.js holds everything that matters: a line-by-line parser (plain text to a worksheet object with warnings) and a generator (worksheet object to one HTML string). The same file runs in the browser and in Node tests.- All teacher text is HTML-escaped. Answer data is embedded as JSON with
< escaped, so worksheet text can never become script (tested).
- The learner runtime is a small ES5 function embedded with
Function.prototype.toString. ES5 and no CSS custom properties give older phone browsers a better chance. The tests parse the embedded script with acorn in ES5 mode.
- The teacher app (
index.html, app.js, app.css) is static and has no backend, no analytics and no external requests. Drafts stay in the browser's localStorage. The preview is the real generated file in a sandboxed iframe.
- Hosted on GitHub Pages.
Testing done
All automated, all in headless Chromium via Playwright. Full output with every number: tests/RESULTS.md. At the time of submission:
- Accessibility scans: axe-core with WCAG 2.2 A/AA and best-practice rules. 12 scans per example file (4 colour schemes, before answering, after answering with feedback and explanations open, and at 200% text with wide spacing): 0 violations across all three files. Teacher app: 0 violations (including the preview frame, the format guide and the problem list), and 0 at 360 px width.
- Keyboard-only walkthrough: the whole fractions worksheet (8 questions: radio, checkbox, typed and open answers, a hint, a wrong answer and retry, the explanation button, reading options) completed with 100 key presses and no mouse. 81 of 81 Tab stops showed a visible focus outline. Progress and settings were restored after reloading.
- Offline: opened from disk in a browser context with the network switched off: 1 request in total (the file itself). Opened from a server then disconnected: still answers and saves. A
fetch() from inside the file is blocked by its own CSP. The teacher app also keeps working after the connection drops.
- File sizes: 22.4 to 24.2 KB per file (about 7 KB zipped).
- Narrow phone viewport (360 × 640): no sideways scrolling at normal text or at 200% text with wide spacing; answer buttons are 50 px tall; tapping works; 0 axe violations.
- Other checks: no-JavaScript fallback, blocked storage, script injection through worksheet text, screen-reader structure (headings, named groups, labels, live regions), parser unit tests.
- Before and after: docs/before-after.md compares Chromium's accessibility tree for a photo of the worksheet (one
img node) with the generated file.
Not tested: no screen-reader users, learners or teachers have used Unscanned. I did not test with a real screen reader (TalkBack, VoiceOver, NVDA or JAWS) or on a real old phone; the accessibility tree is what browsers give screen readers, but how each screen reader announces it can differ. Only Chromium was automated.
Limitations
- Typing is still needed. Unscanned does not read scans or photos (no OCR). The teacher has to type or paste the text. For many teachers the worksheet already exists as typed text, but not for all.
- Maths notation is plain text.
1/2 is read by screen readers as written ("1 slash 2" or similar). There is no support for MathML, diagrams, images, tables or graphs, so worksheets that depend on a picture cannot be converted yet.
- Answer checking is exact matching after simple clean-up. The teacher must list accepted alternatives. Answers are inside the file, so a determined learner can find them: this is for practice, not for tests or grades.
- Interface words are English only. The worksheet itself can be in any language (
Language: sets the code), but buttons such as "Check answer" are in English.
- Read-aloud depends on the device. It uses the browser's speech engine; voices may need internet or may be missing, so it is optional and hidden where unsupported.
- Some chat apps open .html files in a viewer that blocks scripts. The text stays readable, but checking answers needs "Open with" a browser.
- Results stay on the device. There is no way for the teacher to see learners' answers. That keeps it private and offline, but it is a real gap for teachers.
- Old-browser support is designed for (ES5, no CSS variables) but not tested on real old devices.
Credits
- Playwright (Apache-2.0): tests, screenshots and the demo recording.
- axe-core and @axe-core/playwright (MPL-2.0): accessibility scans.
- acorn (MIT): ES5 syntax check.
- FFmpeg (LGPL/GPL): converting the demo video.
- These are development tools only. The app and the generated files use no third-party code, fonts, images or data.
- All three example worksheets, including the short story "The Lamp on the Roof", were written for this project. They are synthetic; no real student data is used anywhere.
AI assistance
Built with an AI coding assistant (Claude); design decisions, testing and write-up reviewed by the author. The assistant wrote most of the code, the example worksheets and the tests under the author's direction.
License
MIT. See LICENSE.
