Use javascript variable in Laravel PHP

Hi i m trying to develop a students registration application with Laravel

a student could be register in many classes each class has a name and level so in registration page i want to show a cheackbox with Classes Name then when i click on a Classe the application show me in the same page a groupe of cheakbox with levels og the cheakes class for exemple if i click on English it shows me Beginin , intermediate ...

So in create.blade.php (register) i have

@foreach ($mat as $m)
{!!Form::label($m->matiere,$m->matiere.' :')!!}
<input type="radio" name="matiere" onclick="cli();" value={!!$m->matiere!!}>
@endforeach 

And i create a Script to help with cli() function

function cli(){       
 classname=document.querySelector('input[name="matiere"]:checked').value;
alert(classname);}

my question is how could i get classnam value in PHP to show the levels of this class

via Chebli Mohamed