onClick Ajax data not working - php

Question

As i'm building an website that needs Ajax for sending POST methods without refreshing the entire page.
I tried using ajax to send data from an onclick event on an LINK-tag, but the ajax code does seem to send an EMPTY post.
This is the php/jquery/ajax code:
<p id="school_content">
</p>
<script src="js/jquery.js"></script>
<script type="text/javascript">
$(document).ready(function() {
$(".toggleThis").click(function(){
var Id = $(this).attr('id');
$.ajax({
contentType: "application/json; charset=utf-8",
url: "id_script.php",
type: "POST",
data: {
'school_name': Id,
},
success: function(data){
alert(Id);
},
});
$("#school_content").load("id_script.php");
});
});
</script>
The LINK-tag has the 'id' of the school of wich the information needs to be shown in the PARAGRAPH with 'id' "school_content" by this jquery part: $("#school_content").load("id_script.php"); .
The var Id = $(this).attr('id'); part works, because he's giving me the right school_name in an alert(); if I ask it to.
The id_script.php needs to get this POST in the usual way, but is does not..
The id_script.php code:
<?php
include('connect.php');
header('Content-Type: application/json');
if(isset($_POST['school_name'])){
$Id = $_POST['school_name'];
$extract = mysqli_query($con, "SELECT * FROM school_kaart WHERE school_name='$Id'");
$numro=mysqli_num_rows($extract);
if(mysqli_num_rows($extract) == '1'){
$row = mysqli_fetch_assoc($extract);
echo 'Yes it works!';
}
else{
echo 'Nope, didnt work!';
}
}
else{
echo 'Not posted!';
}
?>
I'm still getting "Not posted!" in the PARAGRAPH I mentioned earlier. What seems to be the problem?

Answer 1

.load is shorthand for an ajax request so you are actually doing 2 request.
The latter isn't sending any data and so it returns 'Not Posted!';
http://api.jquery.com/load/
try
<script src="js/jquery.js"></script>
<script type="text/javascript">
$(document).ready(function() {
$(".toggleThis").click(function(){
var Id = $(this).attr('id');
$.ajax({
url: "id_script.php",
type: "POST",
data: {
'school_name': Id,
},
success: function(data){
alert(Id);
$("#school_content").html(data);
},
});
//remove this
//$("#school_content").load("id_script.php");
});
});
</script>