diff --git a/app/Models/Guru.php b/app/Models/Guru.php
index 046252b..e191e66 100644
--- a/app/Models/Guru.php
+++ b/app/Models/Guru.php
@@ -10,9 +10,9 @@ class Guru extends Authenticatable
     use HasFactory;
 
     protected $table = 'gurus';
-    protected $primaryKey = 'nip';
-    public $incrementing = false;
-    protected $keyType = 'string';
+    protected $primaryKey = 'id_guru';
+    public $incrementing = true;
+    protected $keyType = 'int';
 
     protected $fillable = [
         'nip',
diff --git a/app/Models/Kelas.php b/app/Models/Kelas.php
index b310993..ec1ce22 100644
--- a/app/Models/Kelas.php
+++ b/app/Models/Kelas.php
@@ -11,8 +11,8 @@ class Kelas extends Model
 
     protected $table = 'kelas'; 
     protected $primaryKey = 'id_kelas';
-    public $incrementing = false;
-    protected $keyType = 'string';
+    public $incrementing = true;
+    protected $keyType = 'int';
 
     protected $fillable = [
         'id_kelas',
diff --git a/app/Models/Leaderboard.php b/app/Models/Leaderboard.php
index d99c558..255f155 100644
--- a/app/Models/Leaderboard.php
+++ b/app/Models/Leaderboard.php
@@ -14,7 +14,7 @@ class Leaderboard extends Model
     protected $primaryKey = 'id_history';
 
     protected $fillable = [
-        'nisn',
+        'id_siswa',
         'id_kelas',
         'total_exp',
         'ranking',
@@ -22,4 +22,14 @@ class Leaderboard extends Model
         'tahun_ajaran',
         'tanggal_snapshot',
     ];
+    
+    public function siswa()
+    {
+        return $this->belongsTo(Siswa::class, 'id_siswa', 'id_siswa'); 
+    }
+
+    public function kelas()
+    {
+        return $this->belongsTo(Kelas::class, 'id_kelas', 'id_kelas');
+    }
 }
\ No newline at end of file
diff --git a/app/Models/Mapel.php b/app/Models/Mapel.php
index a3b2336..db20e5f 100644
--- a/app/Models/Mapel.php
+++ b/app/Models/Mapel.php
@@ -11,8 +11,8 @@ class Mapel extends Model
 
     protected $table = 'mapels';  
     protected $primaryKey = 'id_mapel';
-    public $incrementing = false;
-    protected $keyType = 'string';
+    public $incrementing = true;
+    protected $keyType = 'int';
 
     protected $fillable = [
         'id_mapel',
diff --git a/app/Models/Mengajar.php b/app/Models/Mengajar.php
index f643a39..2062ea9 100644
--- a/app/Models/Mengajar.php
+++ b/app/Models/Mengajar.php
@@ -13,7 +13,7 @@ class Mengajar extends Model
     protected $primaryKey = 'id_mengajar';
 
     protected $fillable = [
-        'nip',
+        'id_guru',
         'id_mapel',
         'id_kelas',
     ];
@@ -21,7 +21,7 @@ class Mengajar extends Model
     // Relasi ke Guru
     public function guru()
     {
-        return $this->belongsTo(Guru::class, 'nip', 'nip');
+        return $this->belongsTo(Guru::class, 'id_guru', 'id_guru');
     }
 
     // Relasi ke Mapel
diff --git a/app/Models/PengumpulanTugas.php b/app/Models/PengumpulanTugas.php
index f540c40..dcb3703 100644
--- a/app/Models/PengumpulanTugas.php
+++ b/app/Models/PengumpulanTugas.php
@@ -15,10 +15,20 @@ class PengumpulanTugas extends Model
 
     protected $fillable = [
         'id_tugas',
-        'nisn',
+        'is_siswa',
         'lampiran_tugas',
         'tanggal_submit',
         'exp',
         'status',
     ];
+
+    public function siswa()
+    {
+        return $this->belongsTo(Siswa::class, 'id_siswa', 'id_siswa'); 
+    }
+
+    public function tugas()
+    {
+        return $this->belongsTo(Tugas::class, 'id_tugas', 'id_tugas');
+    }
 }
\ No newline at end of file
diff --git a/app/Models/PesertaChallenge.php b/app/Models/PesertaChallenge.php
index 0f07eea..feb764a 100644
--- a/app/Models/PesertaChallenge.php
+++ b/app/Models/PesertaChallenge.php
@@ -15,10 +15,20 @@ class PesertaChallenge extends Model
 
     protected $fillable = [
         'id_challenge',
-        'nisn',
+        'id_siswa',
         'jawaban',
         'waktu_submit',
         'exp',
         'status',
     ];
+
+    public function siswa()
+    {
+        return $this->belongsTo(Siswa::class, 'id_siswa', 'id_siswa'); 
+    }
+
+    public function challenge()
+    {
+        return $this->belongsTo(Challenge::class, 'id_challenge', 'id_challenge');
+    }
 }
\ No newline at end of file
diff --git a/app/Models/Siswa.php b/app/Models/Siswa.php
index e008dff..d413490 100644
--- a/app/Models/Siswa.php
+++ b/app/Models/Siswa.php
@@ -11,11 +11,11 @@ class Siswa extends Model
 
     protected $table = 'siswas';
     
-    protected $primaryKey = 'nisn';
+    protected $primaryKey = 'id_siswa';
     
-    public $incrementing = false;
+    public $incrementing = true;
     
-    protected $keyType = 'string';
+    protected $keyType = 'int';
 
     protected $fillable = [
         'nisn',
diff --git a/app/Models/SiswaBadge.php b/app/Models/SiswaBadge.php
index 8d8698b..a281e5f 100644
--- a/app/Models/SiswaBadge.php
+++ b/app/Models/SiswaBadge.php
@@ -14,8 +14,18 @@ class SiswaBadge extends Model
     protected $primaryKey = 'id_siswa_badge';
 
     protected $fillable = [
-        'nisn',
+        'id_siswa',
         'id_badge',
         'tanggal_diberikan',
     ];
+
+    public function siswa()
+    {
+        return $this->belongsTo(Siswa::class, 'id_siswa', 'id_siswa'); 
+    }
+
+    public function badge()
+    {
+        return $this->belongsTo(Badge::class, 'id_badge', 'id_badge');
+    }
 }
\ No newline at end of file
diff --git a/composer.json b/composer.json
index da9c932..38e8622 100644
--- a/composer.json
+++ b/composer.json
@@ -7,6 +7,7 @@
     "license": "MIT",
     "require": {
         "php": "^8.2",
+        "doctrine/dbal": "^4.4",
         "laravel/framework": "^12.0",
         "laravel/tinker": "^2.10.1"
     },
diff --git a/composer.lock b/composer.lock
index ed14c47..e8dd399 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "bdc6d92507d397adf1c269ed49ec424d",
+    "content-hash": "b431c9cde1a46957fa68826ee65622af",
     "packages": [
         {
             "name": "brick/math",
@@ -210,6 +210,160 @@
             },
             "time": "2024-07-08T12:26:09+00:00"
         },
+        {
+            "name": "doctrine/dbal",
+            "version": "4.4.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/doctrine/dbal.git",
+                "reference": "3d544473fb93f5c25b483ea4f4ce99f8c4d9d44c"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/doctrine/dbal/zipball/3d544473fb93f5c25b483ea4f4ce99f8c4d9d44c",
+                "reference": "3d544473fb93f5c25b483ea4f4ce99f8c4d9d44c",
+                "shasum": ""
+            },
+            "require": {
+                "doctrine/deprecations": "^1.1.5",
+                "php": "^8.2",
+                "psr/cache": "^1|^2|^3",
+                "psr/log": "^1|^2|^3"
+            },
+            "require-dev": {
+                "doctrine/coding-standard": "14.0.0",
+                "fig/log-test": "^1",
+                "jetbrains/phpstorm-stubs": "2023.2",
+                "phpstan/phpstan": "2.1.30",
+                "phpstan/phpstan-phpunit": "2.0.7",
+                "phpstan/phpstan-strict-rules": "^2",
+                "phpunit/phpunit": "11.5.23",
+                "slevomat/coding-standard": "8.24.0",
+                "squizlabs/php_codesniffer": "4.0.0",
+                "symfony/cache": "^6.3.8|^7.0|^8.0",
+                "symfony/console": "^5.4|^6.3|^7.0|^8.0"
+            },
+            "suggest": {
+                "symfony/console": "For helpful console commands such as SQL execution and import of files."
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "Doctrine\\DBAL\\": "src"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Guilherme Blanco",
+                    "email": "guilhermeblanco@gmail.com"
+                },
+                {
+                    "name": "Roman Borschel",
+                    "email": "roman@code-factory.org"
+                },
+                {
+                    "name": "Benjamin Eberlei",
+                    "email": "kontakt@beberlei.de"
+                },
+                {
+                    "name": "Jonathan Wage",
+                    "email": "jonwage@gmail.com"
+                }
+            ],
+            "description": "Powerful PHP database abstraction layer (DBAL) with many features for database schema introspection and management.",
+            "homepage": "https://www.doctrine-project.org/projects/dbal.html",
+            "keywords": [
+                "abstraction",
+                "database",
+                "db2",
+                "dbal",
+                "mariadb",
+                "mssql",
+                "mysql",
+                "oci8",
+                "oracle",
+                "pdo",
+                "pgsql",
+                "postgresql",
+                "queryobject",
+                "sasql",
+                "sql",
+                "sqlite",
+                "sqlserver",
+                "sqlsrv"
+            ],
+            "support": {
+                "issues": "https://github.com/doctrine/dbal/issues",
+                "source": "https://github.com/doctrine/dbal/tree/4.4.1"
+            },
+            "funding": [
+                {
+                    "url": "https://www.doctrine-project.org/sponsorship.html",
+                    "type": "custom"
+                },
+                {
+                    "url": "https://www.patreon.com/phpdoctrine",
+                    "type": "patreon"
+                },
+                {
+                    "url": "https://tidelift.com/funding/github/packagist/doctrine%2Fdbal",
+                    "type": "tidelift"
+                }
+            ],
+            "time": "2025-12-04T10:11:03+00:00"
+        },
+        {
+            "name": "doctrine/deprecations",
+            "version": "1.1.6",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/doctrine/deprecations.git",
+                "reference": "d4fe3e6fd9bb9e72557a19674f44d8ac7db4c6ca"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/doctrine/deprecations/zipball/d4fe3e6fd9bb9e72557a19674f44d8ac7db4c6ca",
+                "reference": "d4fe3e6fd9bb9e72557a19674f44d8ac7db4c6ca",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^7.1 || ^8.0"
+            },
+            "conflict": {
+                "phpunit/phpunit": "<=7.5 || >=14"
+            },
+            "require-dev": {
+                "doctrine/coding-standard": "^9 || ^12 || ^14",
+                "phpstan/phpstan": "1.4.10 || 2.1.30",
+                "phpstan/phpstan-phpunit": "^1.0 || ^2",
+                "phpunit/phpunit": "^7.5 || ^8.5 || ^9.6 || ^10.5 || ^11.5 || ^12.4 || ^13.0",
+                "psr/log": "^1 || ^2 || ^3"
+            },
+            "suggest": {
+                "psr/log": "Allows logging deprecations via PSR-3 logger implementation"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "Doctrine\\Deprecations\\": "src"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "description": "A small layer on top of trigger_error(E_USER_DEPRECATED) or PSR-3 logging with options to disable all deprecations or selectively for packages.",
+            "homepage": "https://www.doctrine-project.org/",
+            "support": {
+                "issues": "https://github.com/doctrine/deprecations/issues",
+                "source": "https://github.com/doctrine/deprecations/tree/1.1.6"
+            },
+            "time": "2026-02-07T07:09:04+00:00"
+        },
         {
             "name": "doctrine/inflector",
             "version": "2.1.0",
@@ -2588,6 +2742,55 @@
             ],
             "time": "2025-08-21T11:53:16+00:00"
         },
+        {
+            "name": "psr/cache",
+            "version": "3.0.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/php-fig/cache.git",
+                "reference": "aa5030cfa5405eccfdcb1083ce040c2cb8d253bf"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/php-fig/cache/zipball/aa5030cfa5405eccfdcb1083ce040c2cb8d253bf",
+                "reference": "aa5030cfa5405eccfdcb1083ce040c2cb8d253bf",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=8.0.0"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.0.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Psr\\Cache\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "PHP-FIG",
+                    "homepage": "https://www.php-fig.org/"
+                }
+            ],
+            "description": "Common interface for caching libraries",
+            "keywords": [
+                "cache",
+                "psr",
+                "psr-6"
+            ],
+            "support": {
+                "source": "https://github.com/php-fig/cache/tree/3.0.0"
+            },
+            "time": "2021-02-03T23:26:27+00:00"
+        },
         {
             "name": "psr/clock",
             "version": "1.0.0",
diff --git a/database/migrations/2026_02_18_022905_create_challenge_kelas_table.php b/database/migrations/2026_02_18_022905_create_challenge_kelas_table.php
deleted file mode 100644
index c21b261..0000000
--- a/database/migrations/2026_02_18_022905_create_challenge_kelas_table.php
+++ /dev/null
@@ -1,40 +0,0 @@
-<?php
-
-use Illuminate\Database\Migrations\Migration;
-use Illuminate\Database\Schema\Blueprint;
-use Illuminate\Support\Facades\Schema;
-
-return new class extends Migration
-{
-    /**
-     * Run the migrations.
-     */
-    public function up(): void
-    {
-        Schema::create('challenge_kelas', function (Blueprint $table) {
-    $table->id();
-    $table->unsignedBigInteger('id_challenge');
-    $table->unsignedBigInteger('id_kelas');
-    $table->timestamps();
-
-    $table->foreign('id_challenge')
-          ->references('id_challenge')
-          ->on('challenges')
-          ->onDelete('cascade');
-
-    $table->foreign('id_kelas')
-          ->references('id_kelas')
-          ->on('kelas')
-          ->onDelete('cascade');
-});
-
-    }
-
-    /**
-     * Reverse the migrations.
-     */
-    public function down(): void
-    {
-        Schema::dropIfExists('challenge_kelas');
-    }
-};
diff --git a/database/migrations/2026_02_21_140654_step1_refactor_kelas_pk.php b/database/migrations/2026_02_21_140654_step1_refactor_kelas_pk.php
new file mode 100644
index 0000000..e2f0580
--- /dev/null
+++ b/database/migrations/2026_02_21_140654_step1_refactor_kelas_pk.php
@@ -0,0 +1,38 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+use Illuminate\Support\Facades\DB;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        // FK ke kelas sudah tidak ada, langsung proses
+
+        // 1. Tambah kolom integer sementara
+        Schema::table('kelas', function (Blueprint $table) {
+            $table->unsignedBigInteger('id_kelas_baru')->nullable()->after('id_kelas');
+        });
+
+        // 2. Isi dengan nomor urut
+        DB::statement('SET @n = 0');
+        DB::statement('UPDATE kelas SET id_kelas_baru = (@n := @n + 1) ORDER BY id_kelas');
+
+        // 3. Hapus PK lama (aman karena FK sudah tidak ada)
+        DB::statement('ALTER TABLE kelas DROP PRIMARY KEY');
+
+        // 4. Jadikan AUTO_INCREMENT PK
+        DB::statement('ALTER TABLE kelas MODIFY id_kelas_baru BIGINT UNSIGNED NOT NULL AUTO_INCREMENT, ADD PRIMARY KEY (id_kelas_baru)');
+
+        // 5. Rename kolom
+        DB::statement('ALTER TABLE kelas CHANGE id_kelas id_kelas_old VARCHAR(20)');
+        DB::statement('ALTER TABLE kelas CHANGE id_kelas_baru id_kelas BIGINT UNSIGNED NOT NULL AUTO_INCREMENT');
+    }
+
+    public function down(): void
+    {
+        throw new \Exception('Rollback step ini tidak didukung. Restore dari backup.');
+    }
+};
\ No newline at end of file
diff --git a/database/migrations/2026_02_21_140707_step2_refactor_mapels_pk.php b/database/migrations/2026_02_21_140707_step2_refactor_mapels_pk.php
new file mode 100644
index 0000000..bc9be97
--- /dev/null
+++ b/database/migrations/2026_02_21_140707_step2_refactor_mapels_pk.php
@@ -0,0 +1,38 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+use Illuminate\Support\Facades\DB;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        // FK mengajars_id_mapel_foreign sudah tidak ada, langsung proses
+
+        // 1. Tambah kolom integer sementara
+        Schema::table('mapels', function (Blueprint $table) {
+            $table->unsignedBigInteger('id_mapel_baru')->nullable()->after('id_mapel');
+        });
+
+        // 2. Isi dengan nomor urut
+        DB::statement('SET @n = 0');
+        DB::statement('UPDATE mapels SET id_mapel_baru = (@n := @n + 1) ORDER BY id_mapel');
+
+        // 3. Hapus PK lama
+        DB::statement('ALTER TABLE mapels DROP PRIMARY KEY');
+
+        // 4. Jadikan AUTO_INCREMENT PK
+        DB::statement('ALTER TABLE mapels MODIFY id_mapel_baru BIGINT UNSIGNED NOT NULL AUTO_INCREMENT, ADD PRIMARY KEY (id_mapel_baru)');
+
+        // 5. Rename kolom
+        DB::statement('ALTER TABLE mapels CHANGE id_mapel id_mapel_old VARCHAR(20)');
+        DB::statement('ALTER TABLE mapels CHANGE id_mapel_baru id_mapel BIGINT UNSIGNED NOT NULL AUTO_INCREMENT');
+    }
+
+    public function down(): void
+    {
+        throw new \Exception('Rollback step ini tidak didukung. Restore dari backup.');
+    }
+};
\ No newline at end of file
diff --git a/database/migrations/2026_02_21_140714_step3_refactor_siswas_pk.php b/database/migrations/2026_02_21_140714_step3_refactor_siswas_pk.php
new file mode 100644
index 0000000..96e215f
--- /dev/null
+++ b/database/migrations/2026_02_21_140714_step3_refactor_siswas_pk.php
@@ -0,0 +1,54 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+use Illuminate\Support\Facades\DB;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        // FK ke siswas yang masih ada:
+        // leaderboards_nisn_foreign, pengumpulan_tugas_nisn_foreign,
+        // peserta_challenges_nisn_foreign, siswa_badges_nisn_foreign
+
+        Schema::table('leaderboards', function (Blueprint $table) {
+            $table->dropForeign('leaderboards_nisn_foreign');
+        });
+        Schema::table('pengumpulan_tugas', function (Blueprint $table) {
+            $table->dropForeign('pengumpulan_tugas_nisn_foreign');
+        });
+        Schema::table('peserta_challenges', function (Blueprint $table) {
+            $table->dropForeign('peserta_challenges_nisn_foreign');
+        });
+        Schema::table('siswa_badges', function (Blueprint $table) {
+            $table->dropForeign('siswa_badges_nisn_foreign');
+        });
+
+        // Tambah kolom id_siswa
+        Schema::table('siswas', function (Blueprint $table) {
+            $table->unsignedBigInteger('id_siswa')->nullable()->first();
+        });
+
+        // Isi nomor urut
+        DB::statement('SET @n = 0');
+        DB::statement('UPDATE siswas SET id_siswa = (@n := @n + 1) ORDER BY nisn');
+
+        // Hapus PK nisn
+        DB::statement('ALTER TABLE siswas DROP PRIMARY KEY');
+
+        // Jadikan id_siswa sebagai PK AUTO_INCREMENT
+        DB::statement('ALTER TABLE siswas MODIFY id_siswa BIGINT UNSIGNED NOT NULL AUTO_INCREMENT, ADD PRIMARY KEY (id_siswa)');
+
+        // Jadikan nisn UNIQUE
+        Schema::table('siswas', function (Blueprint $table) {
+            $table->unique('nisn', 'siswas_nisn_unique');
+        });
+    }
+
+    public function down(): void
+    {
+        throw new \Exception('Rollback tidak didukung. Restore dari backup.');
+    }
+};
\ No newline at end of file
diff --git a/database/migrations/2026_02_21_140726_step4_refactor_gurus_pk.php b/database/migrations/2026_02_21_140726_step4_refactor_gurus_pk.php
new file mode 100644
index 0000000..ba82e85
--- /dev/null
+++ b/database/migrations/2026_02_21_140726_step4_refactor_gurus_pk.php
@@ -0,0 +1,42 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+use Illuminate\Support\Facades\DB;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        // FK ke gurus yang masih ada: mengajars_nip_foreign
+        Schema::table('mengajars', function (Blueprint $table) {
+            $table->dropForeign('mengajars_nip_foreign');
+        });
+
+        // Tambah kolom id_guru
+        Schema::table('gurus', function (Blueprint $table) {
+            $table->unsignedBigInteger('id_guru')->nullable()->first();
+        });
+
+        // Isi nomor urut
+        DB::statement('SET @n = 0');
+        DB::statement('UPDATE gurus SET id_guru = (@n := @n + 1) ORDER BY nip');
+
+        // Hapus PK nip
+        DB::statement('ALTER TABLE gurus DROP PRIMARY KEY');
+
+        // Jadikan id_guru sebagai PK AUTO_INCREMENT
+        DB::statement('ALTER TABLE gurus MODIFY id_guru BIGINT UNSIGNED NOT NULL AUTO_INCREMENT, ADD PRIMARY KEY (id_guru)');
+
+        // Jadikan nip UNIQUE
+        Schema::table('gurus', function (Blueprint $table) {
+            $table->unique('nip', 'gurus_nip_unique');
+        });
+    }
+
+    public function down(): void
+    {
+        throw new \Exception('Rollback tidak didukung. Restore dari backup.');
+    }
+};
\ No newline at end of file
diff --git a/database/migrations/2026_02_21_140736_step5_migrate_fk_kelas.php b/database/migrations/2026_02_21_140736_step5_migrate_fk_kelas.php
new file mode 100644
index 0000000..66bb8ae
--- /dev/null
+++ b/database/migrations/2026_02_21_140736_step5_migrate_fk_kelas.php
@@ -0,0 +1,64 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+use Illuminate\Support\Facades\DB;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        // === SISWAS — id_kelas varchar → bigint ===
+        Schema::table('siswas', function (Blueprint $table) {
+            $table->unsignedBigInteger('id_kelas_baru')->nullable()->after('id_kelas');
+        });
+        DB::statement("UPDATE siswas s JOIN kelas k ON s.id_kelas = k.id_kelas_old SET s.id_kelas_baru = k.id_kelas");
+        Schema::table('siswas', function (Blueprint $table) {
+            $table->unsignedBigInteger('id_kelas_baru')->nullable(false)->change();
+            $table->foreign('id_kelas_baru', 'siswas_id_kelas_new_foreign')->references('id_kelas')->on('kelas')->onDelete('cascade');
+        });
+        Schema::table('siswas', function (Blueprint $table) {
+            $table->dropColumn('id_kelas');
+        });
+        DB::statement('ALTER TABLE siswas CHANGE id_kelas_baru id_kelas BIGINT UNSIGNED NOT NULL');
+
+        // === MENGAJARS — id_kelas varchar → bigint ===
+        Schema::table('mengajars', function (Blueprint $table) {
+            $table->unsignedBigInteger('id_kelas_baru')->nullable()->after('id_kelas');
+        });
+        DB::statement("UPDATE mengajars m JOIN kelas k ON m.id_kelas = k.id_kelas_old SET m.id_kelas_baru = k.id_kelas");
+        Schema::table('mengajars', function (Blueprint $table) {
+            $table->unsignedBigInteger('id_kelas_baru')->nullable(false)->change();
+            $table->foreign('id_kelas_baru', 'mengajars_id_kelas_new_foreign')->references('id_kelas')->on('kelas')->onDelete('cascade');
+        });
+        Schema::table('mengajars', function (Blueprint $table) {
+            $table->dropColumn('id_kelas');
+        });
+        DB::statement('ALTER TABLE mengajars CHANGE id_kelas_baru id_kelas BIGINT UNSIGNED NOT NULL');
+
+        // === LEADERBOARDS — id_kelas varchar → bigint ===
+        Schema::table('leaderboards', function (Blueprint $table) {
+            $table->unsignedBigInteger('id_kelas_baru')->nullable()->after('id_kelas');
+        });
+        DB::statement("UPDATE leaderboards l JOIN kelas k ON l.id_kelas = k.id_kelas_old SET l.id_kelas_baru = k.id_kelas");
+        Schema::table('leaderboards', function (Blueprint $table) {
+            $table->unsignedBigInteger('id_kelas_baru')->nullable(false)->change();
+            $table->foreign('id_kelas_baru', 'leaderboards_id_kelas_new_foreign')->references('id_kelas')->on('kelas')->onDelete('cascade');
+        });
+        Schema::table('leaderboards', function (Blueprint $table) {
+            $table->dropColumn('id_kelas');
+        });
+        DB::statement('ALTER TABLE leaderboards CHANGE id_kelas_baru id_kelas BIGINT UNSIGNED NOT NULL');
+
+        // === Hapus kolom id_kelas_old dari kelas ===
+        Schema::table('kelas', function (Blueprint $table) {
+            $table->dropColumn('id_kelas_old');
+        });
+    }
+
+    public function down(): void
+    {
+        throw new \Exception('Rollback tidak didukung. Restore dari backup.');
+    }
+};
\ No newline at end of file
diff --git a/database/migrations/2026_02_21_140744_step6_migrate_fk_mapel.php b/database/migrations/2026_02_21_140744_step6_migrate_fk_mapel.php
new file mode 100644
index 0000000..b840279
--- /dev/null
+++ b/database/migrations/2026_02_21_140744_step6_migrate_fk_mapel.php
@@ -0,0 +1,35 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+use Illuminate\Support\Facades\DB;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::table('mengajars', function (Blueprint $table) {
+            $table->unsignedBigInteger('id_mapel_baru')->nullable()->after('id_mapel');
+        });
+        DB::statement("UPDATE mengajars m JOIN mapels mp ON m.id_mapel = mp.id_mapel_old SET m.id_mapel_baru = mp.id_mapel");
+        Schema::table('mengajars', function (Blueprint $table) {
+            $table->unsignedBigInteger('id_mapel_baru')->nullable(false)->change();
+            $table->foreign('id_mapel_baru', 'mengajars_id_mapel_new_foreign')
+                  ->references('id_mapel')->on('mapels')->onDelete('cascade');
+        });
+        Schema::table('mengajars', function (Blueprint $table) {
+            $table->dropColumn('id_mapel');
+        });
+        DB::statement('ALTER TABLE mengajars CHANGE id_mapel_baru id_mapel BIGINT UNSIGNED NOT NULL');
+
+        Schema::table('mapels', function (Blueprint $table) {
+            $table->dropColumn('id_mapel_old');
+        });
+    }
+
+    public function down(): void
+    {
+        throw new \Exception('Rollback tidak didukung. Restore dari backup.');
+    }
+};
\ No newline at end of file
diff --git a/database/migrations/2026_02_21_140842_step7_migrate_fk_nisn.php b/database/migrations/2026_02_21_140842_step7_migrate_fk_nisn.php
new file mode 100644
index 0000000..80dfb44
--- /dev/null
+++ b/database/migrations/2026_02_21_140842_step7_migrate_fk_nisn.php
@@ -0,0 +1,42 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+use Illuminate\Support\Facades\DB;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        $tables = [
+            'leaderboards',
+            'pengumpulan_tugas',
+            'peserta_challenges',
+            'siswa_badges',
+        ];
+
+        foreach ($tables as $tabel) {
+            Schema::table($tabel, function (Blueprint $table) {
+                $table->unsignedBigInteger('id_siswa')->nullable()->after('nisn');
+            });
+
+            DB::statement("UPDATE {$tabel} t JOIN siswas s ON t.nisn = s.nisn SET t.id_siswa = s.id_siswa");
+
+            Schema::table($tabel, function (Blueprint $table) use ($tabel) {
+                $table->unsignedBigInteger('id_siswa')->nullable(false)->change();
+                $table->foreign('id_siswa', "{$tabel}_id_siswa_new_foreign")
+                      ->references('id_siswa')->on('siswas')->onDelete('cascade');
+            });
+
+            Schema::table($tabel, function (Blueprint $table) {
+                $table->dropColumn('nisn');
+            });
+        }
+    }
+
+    public function down(): void
+    {
+        throw new \Exception('Rollback tidak didukung. Restore dari backup.');
+    }
+};
\ No newline at end of file
diff --git a/database/migrations/2026_02_21_140857_step8_migrate_fk_nip.php b/database/migrations/2026_02_21_140857_step8_migrate_fk_nip.php
new file mode 100644
index 0000000..8eb61b6
--- /dev/null
+++ b/database/migrations/2026_02_21_140857_step8_migrate_fk_nip.php
@@ -0,0 +1,33 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+use Illuminate\Support\Facades\DB;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::table('mengajars', function (Blueprint $table) {
+            $table->unsignedBigInteger('id_guru')->nullable()->after('nip');
+        });
+
+        DB::statement("UPDATE mengajars m JOIN gurus g ON m.nip = g.nip SET m.id_guru = g.id_guru");
+
+        Schema::table('mengajars', function (Blueprint $table) {
+            $table->unsignedBigInteger('id_guru')->nullable(false)->change();
+            $table->foreign('id_guru', 'mengajars_id_guru_new_foreign')
+                  ->references('id_guru')->on('gurus')->onDelete('cascade');
+        });
+
+        Schema::table('mengajars', function (Blueprint $table) {
+            $table->dropColumn('nip');
+        });
+    }
+
+    public function down(): void
+    {
+        throw new \Exception('Rollback tidak didukung. Restore dari backup.');
+    }
+};
\ No newline at end of file
diff --git a/database/migrations/2026_02_21_140910_step9_cleanup_old_varchar_columns.php b/database/migrations/2026_02_21_140910_step9_cleanup_old_varchar_columns.php
new file mode 100644
index 0000000..dde3be4
--- /dev/null
+++ b/database/migrations/2026_02_21_140910_step9_cleanup_old_varchar_columns.php
@@ -0,0 +1,32 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::table('siswas', function (Blueprint $table) {
+            $table->index('id_kelas', 'siswas_id_kelas_index');
+        });
+        Schema::table('mengajars', function (Blueprint $table) {
+            $table->index('id_kelas', 'mengajars_id_kelas_index');
+            $table->index('id_mapel', 'mengajars_id_mapel_index');
+            $table->index('id_guru', 'mengajars_id_guru_index');
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('siswas', function (Blueprint $table) {
+            $table->dropIndex('siswas_id_kelas_index');
+        });
+        Schema::table('mengajars', function (Blueprint $table) {
+            $table->dropIndex('mengajars_id_kelas_index');
+            $table->dropIndex('mengajars_id_mapel_index');
+            $table->dropIndex('mengajars_id_guru_index');
+        });
+    }
+};
\ No newline at end of file
diff --git a/database/migrations/2026_02_21_141000_create_challenge_kelas_table.php b/database/migrations/2026_02_21_141000_create_challenge_kelas_table.php
new file mode 100644
index 0000000..4b09610
--- /dev/null
+++ b/database/migrations/2026_02_21_141000_create_challenge_kelas_table.php
@@ -0,0 +1,39 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+{
+    if (!Schema::hasTable('challenge_kelas')) {
+        Schema::create('challenge_kelas', function (Blueprint $table) {
+            $table->id();
+            $table->unsignedBigInteger('id_challenge');
+            $table->unsignedBigInteger('id_kelas');
+            $table->timestamps();
+            $table->foreign('id_challenge')
+                  ->references('id_challenge')
+                  ->on('challenges')
+                  ->onDelete('cascade');
+            $table->foreign('id_kelas')
+                  ->references('id_kelas')
+                  ->on('kelas')
+                  ->onDelete('cascade');
+        });
+    }
+}
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::dropIfExists('challenge_kelas');
+    }
+};
diff --git a/resources/views/admin/guru/index.blade.php b/resources/views/admin/guru/index.blade.php
index 771fd01..15104a0 100644
--- a/resources/views/admin/guru/index.blade.php
+++ b/resources/views/admin/guru/index.blade.php
@@ -181,7 +181,7 @@
                         <img src="{{ asset('images/icon/main/edit.png') }}" class="action-icon">
                     </button>
 
-                    <form action="{{ route('admin.guru.destroy', $guru->nip) }}" 
+                    <form action="{{ route('admin.guru.destroy', $guru->id_guru) }}" 
                           method="POST" class="d-inline"
                           onsubmit="return confirm('Yakin ingin menghapus data?')">
                         @csrf
diff --git a/resources/views/admin/guru/show.blade.php b/resources/views/admin/guru/show.blade.php
index 7ae5629..449fc7d 100644
--- a/resources/views/admin/guru/show.blade.php
+++ b/resources/views/admin/guru/show.blade.php
@@ -35,7 +35,7 @@
                             <i class="bi bi-arrow-left"></i> Kembali
                         </a>
                         <div>
-                            <a href="{{ route('admin.guru.edit', $guru->nip) }}" class="btn btn-warning text-white">
+                            <a href="{{ route('admin.guru.edit', $guru->id_guru) }}" class="btn btn-warning text-white">
                                 <i class="bi bi-pencil"></i> Edit Data
                             </a>
                         </div>
diff --git a/resources/views/admin/siswa/index.blade.php b/resources/views/admin/siswa/index.blade.php
index e0ec399..c2e5ed3 100644
--- a/resources/views/admin/siswa/index.blade.php
+++ b/resources/views/admin/siswa/index.blade.php
@@ -195,7 +195,7 @@
                         <img src="{{ asset('images/icon/main/edit.png') }}" class="action-icon">
                     </button>
 
-                    <form action="{{ route('admin.siswa.destroy', $siswa->nisn) }}" 
+                    <form action="{{ route('admin.siswa.destroy', $siswa->id_siswa) }}" 
                           method="POST" class="d-inline"
                           onsubmit="return confirm('Yakin ingin menghapus data siswa {{ $siswa->nama }}?')">
                         @csrf