diff --git a/.vscode/settings.json b/.vscode/settings.json
index bc1c7197..19035be5 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -1,3 +1,3 @@
 {
-  "solidity.compileUsingRemoteVersion": "v0.8.14+commit.80d49f37"
+  "solidity.compileUsingRemoteVersion": "v0.8.24+commit.e11b9ed9"
 }
\ No newline at end of file
diff --git a/contracts/IStudentRegistry.sol b/contracts/IStudentRegistry.sol
index b87e8bbe..1db6dae1 100644
--- a/contracts/IStudentRegistry.sol
+++ b/contracts/IStudentRegistry.sol
@@ -1,17 +1,61 @@
 // SPDX-License-Identifier: MIT
 pragma solidity ^0.8.24;
-import "./Student.sol";
+import "contracts/StudentStruct.sol";
+
+/**
+ * @title IStudentRegistry
+ * @dev Interface for the StudentRegistry contract.
+ * Defines the functions available for interacting with the student registry.
+ */
 interface IStudentRegistry {
-    
 
-    function addStudent(
-        address _studentAddr,
-        string memory _name,
-        uint8 _age
-    ) external;
 
-    function getStudent(uint8 _studentID) external view returns (Student memory);
+    /**
+     * @dev pay Fees.
+     */
+    function payFees() external payable;
+
+    /**
+        @notice Withdraws the contract's balance to the owner.
+        @dev This function should handle the transfer of funds from the contract to the owner.
+        @return success A boolean indicating whether the withdrawal was successful.
+    */
+    function withdrawEarnings() external returns (bool);
+
+    /**
+     * @dev Register a student with the provided address, name, and age.
+     * @param _studentAddress The address of the student to register.
+     * @param _name The name of the student.
+     * @param _age The age of the student.
+     */
+    function addStudent(address _studentAddress, string memory _name, uint8 _age) external payable;
+
+    /**
+     * @dev Authorize a student for registration by setting their status to authorized.
+     * @param _studentAddress The address of the student to authorize.
+     */
+    function authorizeStudent(address _studentAddress) external;
+
+    /**
+     * @dev Retrieve a student information.
+     * @param _studentAddress The address of the student to retrieve.
+     */
+    function getStudent(address _studentAddress) external view returns (Student memory);
+
+
+    /**
+     * @dev Update a student record.
+     * @param _studentAddress The new address of the student.
+     * @param _name The new name of the student.
+     * @param _age The new age of the student.
+     */
+    function updateStudent(address _studentAddress, string memory _name, uint8 _age) external;
+
 
-    function getStudentFromMapping(address _studentAddr) external view returns (Student memory);
+    /**
+     * @dev Delete a student record.
+     * @param _studentAddress The address of the student to delete.
+     */
+    function deleteStudent(address _studentAddress) external;
 
-}
+}
\ No newline at end of file
diff --git a/contracts/MyStudentRegistry.sol b/contracts/MyStudentRegistry.sol
deleted file mode 100644
index 10562f12..00000000
--- a/contracts/MyStudentRegistry.sol
+++ /dev/null
@@ -1,31 +0,0 @@
-// SPDX-License-Identifier: GPL-3.0
-pragma solidity >=0.7.0 <0.9.0;
-import "./IStudentRegistry.sol";
-import "./Student.sol";
-import "./Ownable.sol";
-
-contract MyStudentRegistry is Ownable {
-
-    address private StudentRegistryContractAddress;
-
-    constructor(address _studentRgistry){
-        StudentRegistryContractAddress = _studentRgistry;
-    }
-
-    function registerStudent(
-        address _studentAddr,
-        string memory _name,
-        uint8 _age
-    ) public onlyOwner {
-
-        IStudentRegistry(StudentRegistryContractAddress).addStudent(_studentAddr, _name, _age);
-    }
-
-
-    function getStudent2(
-        uint8 _studentId
-    ) public view returns (Student memory) {
-
-        return IStudentRegistry(StudentRegistryContractAddress).getStudent(_studentId);
-    }
-}
diff --git a/contracts/Ownable.sol b/contracts/Ownable.sol
index 624bf251..6e61084b 100644
--- a/contracts/Ownable.sol
+++ b/contracts/Ownable.sol
@@ -1,33 +1,50 @@
-// SPDX-License-Identifier: GPL-3.0
-pragma solidity >=0.7.0 <0.9.0;
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.24;
 
 
 contract Ownable {
 
-    address private owner;
-
-    event ChangeOwner(address indexed oldOwner, address indexed  newOwner);
+    address internal owner;
+    event replaceOwner(address indexed newOwner, address indexed oldOwner, string message);
+  
 
+    /**
+     * @dev Set the owner of the contract to the address deploying the contract.
+     */
     constructor(){
-        owner = msg.sender;
+        owner = payable (msg.sender);
     }
 
 
-    modifier  onlyOwner {
-        require(owner == msg.sender, "Caller not owner");
+    /**
+     * @dev restrict access to the contract owner only.
+     */
+    modifier onlyOwner() {
+        require(owner == msg.sender, "Unauthorized");
         _;
     }
+    
 
+    /**
+     * @dev Retrieve the current owner of the contract.
+     * @return The address of the current owner.
+     */
 
     function getOwner() public  view returns (address){
         return owner;
     }
 
 
-    function changeOwner(address _newOwner) internal onlyOwner {
+
+    /**
+     * @dev Change the owner of the contract to a new address.
+     * @param _newOwner The address of the new owner.
+     * Emits a {changedOwner} event.
+     */
+    function changedOwner(address _newOwner) internal onlyOwner {
         require(_newOwner != address(0), "Owner can not be address zero");
         
-        emit ChangeOwner(owner, _newOwner);
+        emit replaceOwner(_newOwner, owner, "This owner has been changed");
         owner = _newOwner;
     }
 }
\ No newline at end of file
diff --git a/contracts/Payment.sol b/contracts/Payment.sol
new file mode 100644
index 00000000..5c0ba48d
--- /dev/null
+++ b/contracts/Payment.sol
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.24;
+
+import "./StudentStruct.sol";
+import "./modifiers/Ownable.sol";
+import "./modifiers/InputValidations.sol";
+
+/**
+ * @title student Payment
+ * @dev This contract manages student registration payment, authorization, and details.
+ * It handles student registration payment.
+ */
+contract Payment is Ownable, InputValidation {
+
+    event PaymentStatus(bool indexed hasPaid, string message);
+
+    // Mapping of student address to payment receipt amount
+    mapping  (address => uint256) internal PaymentDetails;
+   
+
+   // Make payment
+    function payFees() public payable {
+        uint256 amount = msg.value;
+        require(amount == 1 ether, "1 eth is required");
+         PaymentDetails[msg.sender] = amount;
+        emit PaymentStatus(true, "Payment successful!!");
+    }
+
+     /**
+        @notice Withdraws the contract's balance to the owner's address.
+        @return withdrawal indicating the withdrawal was successful.
+    */
+    function withdrawEarnings() public onlyOwner returns(bool)  {
+        // get the amount of Ether stored in this contract
+        uint256 amount = address(this).balance;
+        require(amount > 0, "Empty Balance");
+        // send all Ether to owner
+        (bool withdrawal,) = owner.call{value: amount}("");
+        require(withdrawal, "Failed to send Ether");
+        return withdrawal;
+    }
+
+    // Function to transfer Ether from this contract to address from input
+    function transfer(address payable _to, uint256 _amount) public onlyOwner {
+        (bool success,) = _to.call{value: _amount}("");
+        require(success, "Failed to send Ether");
+    }
+}
\ No newline at end of file
diff --git a/contracts/Student.sol b/contracts/Student.sol
deleted file mode 100644
index f7246ea0..00000000
--- a/contracts/Student.sol
+++ /dev/null
@@ -1,8 +0,0 @@
- // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.24;
- struct Student {
-        address studentAddr;
-        string name;
-        uint256 studentId;
-        uint8 age;
-    }
diff --git a/contracts/StudentRegistry.sol b/contracts/StudentRegistry.sol
index 591618e1..a4a0c1dc 100644
--- a/contracts/StudentRegistry.sol
+++ b/contracts/StudentRegistry.sol
@@ -1,96 +1,86 @@
 // SPDX-License-Identifier: MIT
 pragma solidity ^0.8.24;
-import "./Ownable.sol";
-import "./Student.sol";
-
 
+import "contracts/modifiers/Ownable.sol";
+import "./IStudentRegistry.sol";
+/**
+ * @title MyStudentRegistry
+ * @dev This contract acts as a proxy to interact with another StudentRegistry contract.
+ * It forwards calls to the `StudentRegistry` contract for student management functions.
+ */
 contract StudentRegistry is Ownable {
-    //custom erros
-    error NameIsEmpty();
-    error UnderAge(uint8 age, uint8 expectedAge);
-
-    //custom data type
-   
-  
-    //dynamic array of students
-    Student[] private students;
-
-    mapping(address => Student) public studentsMapping;
-
-
-    modifier isNotAddressZero() {
-        require(msg.sender != address(0), "Invalid Address");
-        _;
+    address public studentsContractAddress;
+
+    /**
+     * @dev Set the address of the Students contract.
+     * @param _studentsContractAddr The address of the Student contract.
+     */
+    constructor(address _studentsContractAddr) {
+        studentsContractAddress = _studentsContractAddr;
     }
 
-    function addStudent(
-        address _studentAddr,
-        string memory _name,
-        uint8 _age
-    ) public  isNotAddressZero {
-        if (bytes(_name).length == 0) {
-            revert NameIsEmpty();
-        }
-
-        if (_age < 18) {
-            revert UnderAge({age: _age, expectedAge: 18});
-        }
-
-        uint256 _studentId = students.length + 1;
-        Student memory student = Student({
-            studentAddr: _studentAddr,
-            name: _name,
-            age: _age,
-            studentId: _studentId
-        });
-
-        students.push(student);
-        // add student to studentsMapping
-        studentsMapping[_studentAddr] = student;
+    /**
+     * @dev Register a student.
+     * @param _studentAddress The address of the student to register.
+     * @param _name The name of the student.
+     * @param _age The age of the student.
+     */
+    function addStudents(address _studentAddress, string memory _name, uint8 _age) public  {
+        IStudentRegistry(studentsContractAddress).addStudent(_studentAddress, _name, _age);
     }
 
-    function getStudent(uint8 _studentId)
-        public
-        view
-        isNotAddressZero
-        returns (Student memory)
-    {
-        return students[_studentId - 1];
+    /**
+     * @dev Retrieve a student record.
+     * @param _studentAddr The address of the student to retrieve.
+     */
+    function getStudents(address _studentAddr) public view returns (Student memory) {
+        return IStudentRegistry(studentsContractAddress).getStudent(_studentAddr);
     }
 
-    function getStudentFromMapping(address _studentAddr)
-        public
-        view
-        isNotAddressZero
-        returns (Student memory)
-    {
-        return studentsMapping[_studentAddr];
+    /**
+     * @dev Update a student record.
+     * @param _studentAddr The new address of the student.
+     * @param _name The new name of the student.
+     * @param _age The new age of the student.
+     */
+    function updateStudents(
+        address _studentAddr, 
+        string memory _name, 
+        uint8 _age
+    ) public {
+        IStudentRegistry(studentsContractAddress).updateStudent(_studentAddr, _name, _age);
     }
 
-    function deleteStudent(address _studentAddr)
-        public
-        onlyOwner
-        isNotAddressZero
-    {
-        require(
-            studentsMapping[_studentAddr].studentAddr != address(0),
-            "Student does not exist"
-        );
 
-        // delete studentsMapping[_studentAddr];
+     /**
+     * @dev Delete a student record.
+     * @param _studentAddr The address of the student to delete.
+     * @notice  only owner can delete a student
+     */
+    function removeStudent(address _studentAddr) public {
+        IStudentRegistry(studentsContractAddress).deleteStudent(_studentAddr);
+    }
 
-        Student memory student = Student({
-            studentAddr: address(0),
-            name: "",
-            age: 0,
-            studentId: 0
-        });
 
-        studentsMapping[_studentAddr] = student;
+    /**
+        @notice Pay Fees.
+        @dev This function calls the payFees function in the external contract..
+    */
+    function payFees() public payable  {
+        return IStudentRegistry(studentsContractAddress).payFees{value: msg.value}();
     }
 
-
-    function modifyOwner(address _newOwner) public {
-        changeOwner(_newOwner);
+        /**
+        @notice Withdraws the contract's balance from the external Student Registry contract.
+        @dev This function calls the withdraw function in the external contract.
+        @return success A boolean value indicating whether the withdrawal was successful.
+    */
+    function withdrawEarnings() public returns (bool) {
+        return IStudentRegistry(studentsContractAddress).withdrawEarnings();
     }
-}
+
+    /**
+     * @dev Allow the contract to receive Ether.
+     */
+    receive() external payable { }
+}
\ No newline at end of file
diff --git a/contracts/StudentStruct.sol b/contracts/StudentStruct.sol
new file mode 100644
index 00000000..a282bf60
--- /dev/null
+++ b/contracts/StudentStruct.sol
@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.24;
+
+/**
+ * @title Student
+ * @dev A Struct containing student information.
+ */
+struct Student {
+    /**
+     * @dev The address of the student.
+     */
+    address studentAddress;
+
+    /**
+     * @dev The unique ID assigned to the student.
+     */
+    uint256 studentId;
+
+    /**
+     * @dev The name of the student.
+     */
+    string name;
+
+    /**
+     * @dev The age of the student.
+     */
+    uint8 age;
+
+    /**
+     * @dev student authorization status.
+     */
+    bool hasPaid;
+}
diff --git a/contracts/Students.sol b/contracts/Students.sol
new file mode 100644
index 00000000..f8ae2286
--- /dev/null
+++ b/contracts/Students.sol
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.24;
+
+import "./StudentStruct.sol";
+import "./modifiers/Ownable.sol";
+import "./modifiers/InputValidations.sol";
+import "./Payment.sol";
+
+
+
+/**
+ * @title Students
+ * @dev This contract manages student registrations, authorization, and details.
+ * It allows for student registration with payment, updating student information, and handling ownership.
+ */
+contract Students is Payment, InputValidation, Ownable {
+   event createEvent(address indexed  studentAddress, string message);
+   event updateEvent(address indexed  studentAddress, string message);
+    // Mapping of student address to their details
+    mapping (address => Student) private students;
+    uint256 private  studentCount = 0;
+    
+
+    /**
+     * @dev Register a student with a given address, name, and age.
+     * Requires payment of exactly 1 ether.
+     * @param _studentAddress The address of the student.
+     * @param _name The name of the student.
+     * @param _age The age of the student.
+     */
+    
+    function addStudent(address _studentAddress, string memory _name, uint8 _age) public validateAddress(_studentAddress) validateStudentAge(_age) validateStudentName(_name) onlyOwner {
+      
+        uint256 hasPaid = PaymentDetails[_studentAddress];
+
+        require(hasPaid > 0 ether, "payment required");
+
+        uint256 _studentId = studentCount + 1;
+        Student memory student = Student({
+            studentAddress: _studentAddress,
+            name: _name,
+            age: _age,
+            studentId: _studentId,
+            hasPaid:true
+        });
+
+        // add student to students Mapping
+        students[_studentAddress] = student;
+        emit createEvent(_studentAddress, "student added");
+    }
+
+    /**
+     * @dev Retrieve the student by address.
+     * @return The student record.
+     */
+    function getStudent(address _studentaddr)
+        public
+        view
+        validateAddress(_studentaddr)
+        returns (Student memory)
+    {  
+        require(students[_studentaddr].studentAddress != address(0), "student does not exist");
+        return students[_studentaddr];
+    }
+
+
+
+    /**
+     * @dev Delete a student record. Only the owner can delete a student.
+     * @param _studentAddr The address of the student to delete.
+     */
+    function deleteStudent(address _studentAddr)
+        public
+        onlyOwner
+        validateAddress(_studentAddr)
+    {
+        require(
+            students[_studentAddr].studentAddress != address(0),
+            "Student does not exist"
+        );
+
+        delete students[_studentAddr];
+    }
+
+
+
+    /**
+     * @dev Update student record.
+     * Can change name, or age of the student. Only the owner can update.
+     * @param _studentAddr The new address of the student.
+     * @param _name The new name of the student.
+     * @param _age The new age of the student.
+     */
+    function updateStudent(
+        address _studentAddr,
+        string memory _name,
+        uint8 _age
+    ) public validateAddress(_studentAddr) {
+require(
+            students[_studentAddr].studentAddress != address(0),
+            "Student does not exist"
+        );
+
+        Student memory student = students[_studentAddr];
+        student.name = _name;
+        student.age = _age;
+        students[_studentAddr] = student;
+         emit updateEvent(_studentAddr, "update successful");
+    }
+
+    /**
+     * @dev Allow the contract to receive Ether.
+     */
+    receive() external payable { }
+}
\ No newline at end of file
diff --git a/contracts/modifiers/InputValidations.sol b/contracts/modifiers/InputValidations.sol
new file mode 100644
index 00000000..2b038679
--- /dev/null
+++ b/contracts/modifiers/InputValidations.sol
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.24;
+
+/**
+* @title Input Validation Contract
+* @notice This contract contains modifiers to validate inputs for student registration
+*/
+contract InputValidation {
+    /**
+     *@dev Ensures that the student is at least 18 years old.
+     * @notice Modifier to validate the age of the student
+     *@param _age The age of the student
+     */
+    modifier validateStudentAge(uint256 _age) {
+        require( _age >= 18, "This student is under age");
+        _;
+    }
+
+  
+    /**
+     *@dev Ensures that the name is not blank.
+     * @notice Modifier to validate the name of the student
+     * @param _name The name of the student
+     */
+    modifier validateStudentName(string memory _name) {
+       require( bytes(_name).length > 0, "Name cannot be blank");
+        _;
+    }
+
+     /**
+     * @dev Ensures that the student ID is greater than zero.
+     * @notice Modifier to validate the ID of the student
+     * @param _studentId The ID of the student
+     */
+    modifier validateStudentId(uint8 _studentId) {
+        require(_studentId > 0, "Invalid Student ID");
+        _;
+    }
+
+   
+    /**
+     * @dev Ensures that the address is not the zero address.
+     * @notice Modifier to validate the address of the student
+     * @param _studentAddr The address of the student
+     */
+     modifier validateAddress(address _studentAddr) {
+        require( _studentAddr != address(0), "Invalid Address");
+        _;
+    }
+}
\ No newline at end of file
diff --git a/contracts/modifiers/Ownable.sol b/contracts/modifiers/Ownable.sol
new file mode 100644
index 00000000..6e61084b
--- /dev/null
+++ b/contracts/modifiers/Ownable.sol
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.24;
+
+
+contract Ownable {
+
+    address internal owner;
+    event replaceOwner(address indexed newOwner, address indexed oldOwner, string message);
+  
+
+    /**
+     * @dev Set the owner of the contract to the address deploying the contract.
+     */
+    constructor(){
+        owner = payable (msg.sender);
+    }
+
+
+    /**
+     * @dev restrict access to the contract owner only.
+     */
+    modifier onlyOwner() {
+        require(owner == msg.sender, "Unauthorized");
+        _;
+    }
+    
+
+    /**
+     * @dev Retrieve the current owner of the contract.
+     * @return The address of the current owner.
+     */
+
+    function getOwner() public  view returns (address){
+        return owner;
+    }
+
+
+
+    /**
+     * @dev Change the owner of the contract to a new address.
+     * @param _newOwner The address of the new owner.
+     * Emits a {changedOwner} event.
+     */
+    function changedOwner(address _newOwner) internal onlyOwner {
+        require(_newOwner != address(0), "Owner can not be address zero");
+        
+        emit replaceOwner(_newOwner, owner, "This owner has been changed");
+        owner = _newOwner;
+    }
+}
\ No newline at end of file