SubtractEd

Strategic intervention material for Grade 7 learners who are learning to subtract integers. A learner moves through a guide, three activities, an assessment, and an enrichment crossword. Progress stays on the device, and the app installs as a PWA and caches the lesson for offline use.

Open SubtractEd

Developed by Harry Arnold C. Salele and Imae Cuesta at Biliran Province State University.

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The four cards

1. Guide. The competency, the three objectives, and a short video.
2. Activities, unlocked in order:
   • integer chips
   • a number line
   • the Keep-Change-Change rule for numerals
3. Assessment. A quiz on subtracting integers.
4. Enrichment. Six crossword levels, from filling a missing whole number to subtracting a negative.

Finishing a card unlocks the next one. Progress can be reset from the home screen.

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Stack

Layer	Choice
Web	React 19 + TypeScript, Vite, installable as a PWA
API	Express 5
Hosting	Vercel

The cards run in the browser. Progress is stored on the device. The Express process answers a health check at GET / and is not called by the app.

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Getting started

Requires Node.js and npm.

npm run install:all
npm run dev

The app is at http://localhost:5173. The API listens on http://localhost:5000.

To run the app on its own:

npm install --prefix client
npm run dev --prefix client

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Layout

subtract-ed/
├── client/    React PWA — cards, activities, assessment, enrichment
└── server/    Express health check

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Live

Application	https://subtract-ed.vercel.app