add poker planing for students

app/Models/EstimationRound.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Model;
+
+class EstimationRound extends Model
+{
+    protected $fillable = ['token', 'max_score', 'max_voters'];
+
+    public function votes()
+    {
+        return $this->hasMany(Vote::class);
+    }
+
+    public function getAverageScoreAttribute()
+    {
+        return $this->votes->avg('score');
+    }
+}