📚 Student Grading System Smart Contract

This Solidity project implements a decentralized Student Grading System where:

• The Principal (Owner) deploys the contract and assigns Teachers.
• Teachers (Admins) are allowed to add students’ scores and associate them with subjects.
• Students can view their individual scores and grade remarks by subject.
• Teachers and Principal can view all the student records across subjects.

✅ This contract does not use OpenZeppelin libraries — all access control is handled with custom logic and modifiers.

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🚀 Features

• 👑 Principal Role:

  • Deploys the contract.
  • Assigns teacher addresses.

• 👨‍🏫 Teacher/Admin Role:

  • Adds student grades per subject.
  • Can view all students’ records.

• 👩‍🎓 Student Role:

  • Views their subject-specific score, grade, and remark.

• 🧾 Grading Logic:

  • Automatically assigns:

    • A: 70–100 ✅
    • B: 60–69 ✅
    • C: 50–59 ✅
    • D: 40–49 ✅
    • F: below 40 ❌

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🏗️ Contract Structure

• Structs:

  • Student: contains name, subjects, scores, and grades.
  • Score: encapsulates subject, marks, grade.

• Mappings:

  • students: maps student addresses to their record.
  • teachers: maps teacher addresses to boolean.

• Modifiers:

  • onlyPrincipal: restricts actions to the contract owner.
  • onlyTeacher: restricts score input to verified teachers.
  • onlyStudent: for student-specific views.
  • onlyAdmin: for teachers or the principal.

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🔍 How It Works

1. Principal assigns one or more teacher addresses.

2. Teachers add student scores using:

   addStudentScore(studentAddress, studentName, subject, score)

3. Students view their result by calling:

   viewMyGradeBySubject("Mathematics")

4. Admin can retrieve all student results via:

   getStudentRecords(studentAddress)

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🧪 Testing

This project includes comprehensive tests written in Foundry to ensure:

• Role-based restrictions are enforced.
• Score grading is accurate.
• Students can only access their records.
• Admins can view all records.

Run test with:

forge test

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📁 Project Structure

├── src/
│   └── StudentGradingSystem.sol
├── test/
│   └── StudentGradingSystemTest.t.sol
├── foundry.toml
└── README.md

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📜 License

MIT License

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🙌 Acknowledgements

This contract was written and tested as part of a blockchain education cohort focused on building real-world decentralized applications using Solidity and Foundry.