User model inheritance

I would like to extend the User model to simplify login and to separate different relationships between shared models.

I've included my setup below. I am having difficulties in how I should access the logged in User's modules / module depending on whether they are a Student or a Teacher.

User model

This is the generic (untouched) User model.

Student model

<?php

namespace App;

class Student extends User
{

    public function modules()
    {
        return $this->belongsToMany(Module::class);
    }
}

Teacher model

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Teacher extends Model
{
    public function module()
    {
        $this->hasMany(Module::class);
    }
}

Module model

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\SoftDeletes;

class Module extends Model
{
    use SoftDeletes;

    protected $fillable = [
        'module_code',
        'name',
        'description',
        'color'
    ];

    public function students()
    {
        return $this->belongsToMany(Student::class);
    }

    public function teacher()
    {
        return $this->belongsTo(Teacher::class);
    }
}