CREATE TABLE Students (
    StudentID INT PRIMARY KEY AUTO_INCREMENT,
    student_name VARCHAR(100) NOT NULL,
    age INT,
    grade CHAR(1)
);

CREATE TABLE Quizzes (
    QuizID INT PRIMARY KEY AUTO_INCREMENT,
    quiz_name VARCHAR(100) NOT NULL,
    quiz_date DATE
);

CREATE TABLE Questions (
    QuestionID INT PRIMARY KEY AUTO_INCREMENT,
    QuizID INT,
    question_text TEXT NOT NULL,
    FOREIGN KEY (QuizID) REFERENCES Quizzes(QuizID)
);

CREATE TABLE Answers (
    AnswerID INT PRIMARY KEY AUTO_INCREMENT,
    QuestionID INT,
    answer_text TEXT NOT NULL,
    is_correct BOOLEAN NOT NULL,
    FOREIGN KEY (QuestionID) REFERENCES Questions(QuestionID)
);

CREATE TABLE Responses (
    ResponseID INT PRIMARY KEY AUTO_INCREMENT,
    StudentID INT,
    AnswerID INT,
    response_date DATE,
    FOREIGN KEY (StudentID) REFERENCES Students(StudentID),
    FOREIGN KEY (AnswerID) REFERENCES Answers(AnswerID)
);

CREATE TABLE Grades (
    GradeID INT PRIMARY KEY AUTO_INCREMENT,
    StudentID INT,
    QuizID INT,
    grade CHAR(1),
    FOREIGN KEY (StudentID) REFERENCES Students(StudentID),
    FOREIGN KEY (QuizID) REFERENCES Quizzes(QuizID)
);

INSERT INTO Students (student_name, age, grade)
VALUES 
('John Doe', 20, 'B'),
('Jane Smith', 22, 'A'),
('Mark Johnson', 21, 'C'),
('Sara Lee', 23, 'B'),
('Tom Brown', 19, 'A');

INSERT INTO Quizzes (quiz_name, quiz_date)
VALUES 
('Math Quiz', '2023-05-15'),
('Physics Quiz', '2023-06-10'),
('History Quiz', '2023-07-01'),
('Chemistry Quiz', '2023-08-25'),
('Biology Quiz', '2023-09-12');

INSERT INTO Questions (QuizID, question_text)
VALUES 
(1, 'What is 2 + 2?'),
(1, 'What is 3 + 5?'),
(2, 'What is Newton\'s first law?'),
(3, 'Who discovered America?'),
(4, 'What is the chemical symbol for water?');

INSERT INTO Answers (QuestionID, answer_text, is_correct)
VALUES 
(1, '4', TRUE),
(1, '5', FALSE),
(2, '8', TRUE),
(2, '7', FALSE),
(3, 'An object in motion stays in motion', TRUE),
(3, 'Energy cannot be created or destroyed', FALSE),
(4, 'Christopher Columbus', TRUE),
(4, 'Amerigo Vespucci', FALSE),
(5, 'H2O', TRUE),
(5, 'CO2', FALSE);

INSERT INTO Responses (StudentID, AnswerID, response_date)
VALUES 
(1, 1, '2023-05-15'),
(1, 3, '2023-05-15'),
(2, 2, '2023-06-10'),
(2, 4, '2023-06-10'),
(3, 5, '2023-07-01');

INSERT INTO Grades (StudentID, QuizID, grade)
VALUES 
(1, 1, 'B'),
(1, 2, 'A'),
(2, 1, 'A'),
(3, 3, 'C'),
(4, 4, 'B');