änderungen zuammengeführt

app/Models/Belt.php

@@ -0,0 +1,17 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsToMany;
+
+class Belt extends Model
+{
+    protected $fillable = ["name"];
+
+    public function courses(): BelongsToMany
+    {
+        return $this->belongsToMany(Course::class);
+    }
+
+}

app/Models/Course.php

@@ -0,0 +1,23 @@
+<?php
+
+namespace App\Models;
+
+use App\Models\Kid;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsToMany;
+
+class Course extends Model
+{
+    protected $fillable = ["name", "duration"];
+
+    public function kids(): BelongsToMany
+    {
+        return $this->belongsToMany(Kid::class)->withPivot("date");
+    }
+
+    public function belts(): BelongsToMany
+    {
+        return $this->belongsToMany(Belt::class);
+    }
+
+}

app/Models/Kid.php

@@ -0,0 +1,16 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsToMany;
+
+class Kid extends Model
+{
+    protected $fillable = ["name", "email"];
+
+    public function courses(): BelongsToMany
+    {
+        return $this->belongsToMany(Course::class)->withPivot("date");
+    }
+}