protected function migrateClassrooms()
    {
        $this->output->info('### Migrating classrooms ###');
        foreach ($classrooms = $this->classrooms() as $classroom) {
            $this->showMigratingInfo($classroom, 1);
            $this->migrateClassroom($classroom);
        }
        $this->output->info(
            '### END Migrating classrooms. Migrated ' . count($classrooms) .  ' locations   ###');
    }