Note that you should make sure that queries is safe agains database injection. The best way is probably prepared queries since you use mysqli functions. Unfortunately I can't show you since I don't know how to use them myself.
Based on what the PHP Manual says on mysqli prepared statements, I think it would be:
$sql = "INSERT INTO faculty_mod1 (fname, lname, center, score1, date1)
VALUES (?, ?, ?, ?, ?)";
if ($stmt = mysqli_prepare($mysqli, $sql)) {
mysqli_stmt_bind_param($stmt, 'sssds',
$_POST["fname"],
$_POST["lname"],
$_POST["center"],
$_POST["score1"],
$today["date1"]);
mysqli_stmt_execute($stmt);
}
What I am not clear about is what is the type to use for a datetype.