while ($res = $result->fetch_assoc()) {
        echo "<tr><td>" . $res['subname'] . "</td>";

        $result2 = mysqli_query($mysqli, "SELECT *
                                            FROM grades
                                            JOIN gradesets ON grades.gradeset_id = gradesets.id
                                            WHERE grades.student_id = {$row['id']}
                                            AND grades.subject_id = {$res['id']}
                                            ORDER BY grades.gradeset_id ") or die($mysqli->error);

        while ($res2 = $result2->fetch_assoc()) {

            echo "<td>" . $res2['grade'] . "</td>";
            //echo "<td>" . $res2['gradeset_id'] . "</td>";
            //print_r($res2);
            $resset = $res2['gradeset'];
            $resset2 = substr($resset, -1);
            //print_r($resset);
            //print_r($resset2);

        }
    }

$student = $mysqli->query("SELECT * FROM student");

echo "<center>";
echo "<h2>Data Wall</h2>";
echo "<h3>PHP</h3>";
echo "<hr/>";

while ($row = $student->fetch_assoc()) {
    echo "<table border='1'>
            <tr>
                <th>ID</th>
                <th>STUDENT</th>
                <th>HOUSE</th>
            </tr><br>";
    echo "<tr>";
    echo "<td>" . $row['id'] . "</td>";
    echo "<td>" . $row['stuname'] . "</td>";
    echo "<td>" . $row['house'] . "</td>";
    echo "</tr><br><tr></tr><tr></tr><tr></tr><tr></tr><tr></tr><tr></tr><tr></tr>";
    echo "<tr><th>SUBJECTS</th><th>PC1</th><th>PC2</th><th>PC3</th><th>PC4</th></tr>";
    $result = mysqli_query($mysqli, "SELECT  subjects.id,subjects.subname
                                    FROM student
                                    JOIN grades ON student.id = grades.student_id
                                    JOIN subjects ON subjects.id = grades.subject_id
                                    WHERE student.id = {$row['id']}
                                    GROUP BY subjects.subname ORDER BY subjects.id ") or die($mysqli->error);

    while ($res = $result->fetch_assoc()) {
        echo "<tr><td>" . $res['subname'] . "</td>";

        $result2 = mysqli_query($mysqli, "SELECT *
                                            FROM grades
                                            JOIN gradesets ON grades.gradeset_id = gradesets.id
                                            WHERE grades.student_id = {$row['id']}
                                            AND grades.subject_id = {$res['id']}
                                            ORDER BY grades.gradeset_id ") or die($mysqli->error);

        while ($res2 = $result2->fetch_assoc()) {

            echo "<td>" . $res2['grade'] . "</td>";
            //echo "<td>" . $res2['gradeset_id'] . "</td>";
            //print_r($res2);
            $resset = $res2['gradeset'];
            $resset2 = substr($resset, -1);
            //print_r($resset);
            //print_r($resset2);

        }
    }
}
echo "</tr>";
echo "</table>";
echo "</center>";
$mysqli->close();
?>