diff --git a/app/Rules/UniqueFullNameAtSchool.php b/app/Rules/UniqueFullNameAtSchool.php
index 29e78ad..9c34dbd 100644
--- a/app/Rules/UniqueFullNameAtSchool.php
+++ b/app/Rules/UniqueFullNameAtSchool.php
@@ -5,12 +5,15 @@ namespace App\Rules;
 use App\Models\Student;
 use Closure;
 use Illuminate\Contracts\Validation\ValidationRule;
+use Illuminate\Translation\PotentiallyTranslatedString;
 
 class UniqueFullNameAtSchool implements ValidationRule
 {
-    protected $first_name;
-    protected $last_name;
-    protected $school_id;
+    protected string $first_name;
+
+    protected string $last_name;
+
+    protected int $school_id;
 
     public function __construct($firstName, $lastName, $schoolID)
     {
@@ -19,7 +22,7 @@ class UniqueFullNameAtSchool implements ValidationRule
         $this->school_id = $schoolID;
     }
 
-    public function studentExists()
+    public function studentExists(): bool
     {
         return Student::where('first_name', $this->first_name)
             ->where('last_name', $this->last_name)
@@ -27,18 +30,19 @@ class UniqueFullNameAtSchool implements ValidationRule
             ->exists();
     }
 
-    public function message()
+    public function message(): string
     {
-        return "There is already a student with that name at the school you are trying to add them to";
+        return 'There is already a student with that name at the school you are trying to add them to';
     }
+
     /**
      * Run the validation rule.
      *
-     * @param  \Closure(string): \Illuminate\Translation\PotentiallyTranslatedString  $fail
+     * @param  Closure(string): PotentiallyTranslatedString  $fail
      */
     public function validate(string $attribute, mixed $value, Closure $fail): void
     {
-        if($this->studentExists()) {
+        if ($this->studentExists()) {
             $fail($this->message());
         }
     }
diff --git a/tests/Feature/app/Rules/UniqueFullNameAtSchoolTest.php b/tests/Feature/app/Rules/UniqueFullNameAtSchoolTest.php
new file mode 100644
index 0000000..c92b5ba
--- /dev/null
+++ b/tests/Feature/app/Rules/UniqueFullNameAtSchoolTest.php
@@ -0,0 +1,75 @@
+<?php
+
+use App\Models\School;
+use App\Models\Student;
+use App\Rules\UniqueFullNameAtSchool;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+
+uses(RefreshDatabase::class);
+
+describe('UniqueFullNameAtSchool validation rule', function () {
+    it('fails validation when student with same name exists at school', function () {
+        // Arrange
+        $school = School::factory()->create();
+        Student::factory()->create([
+            'first_name' => 'John',
+            'last_name' => 'Doe',
+            'school_id' => $school->id,
+        ]);
+
+        $rule = new UniqueFullNameAtSchool('John', 'Doe', $school->id);
+        $fails = false;
+
+        // Act
+        $rule->validate('name', 'value', function ($message) use (&$fails) {
+            $fails = true;
+        });
+
+        // Assert
+        expect($fails)->toBeTrue()
+            ->and($rule->message())->toBe('There is already a student with that name at the school you are trying to add them to');
+    });
+
+    it('passes validation when no student with same name exists at school', function () {
+        // Arrange
+        $school = School::factory()->create();
+        Student::factory()->create([
+            'first_name' => 'Jane',
+            'last_name' => 'Doe',
+            'school_id' => $school->id,
+        ]);
+
+        $rule = new UniqueFullNameAtSchool('John', 'Doe', $school->id);
+        $fails = false;
+
+        // Act
+        $rule->validate('name', 'value', function ($message) use (&$fails) {
+            $fails = true;
+        });
+
+        // Assert
+        expect($fails)->toBeFalse();
+    });
+
+    it('passes validation when student with same name exists at different school', function () {
+        // Arrange
+        $school1 = School::factory()->create();
+        $school2 = School::factory()->create();
+        Student::factory()->create([
+            'first_name' => 'John',
+            'last_name' => 'Doe',
+            'school_id' => $school1->id,
+        ]);
+
+        $rule = new UniqueFullNameAtSchool('John', 'Doe', $school2->id);
+        $fails = false;
+
+        // Act
+        $rule->validate('name', 'value', function ($message) use (&$fails) {
+            $fails = true;
+        });
+
+        // Assert
+        expect($fails)->toBeFalse();
+    });
+});