public function print_teacher_table() {
        $table = new html_table();
        $table->head = array(get_string('coursename', 'grades'));
        $table->data = null;
        foreach ($this->teachercourses as $courseid => $course) {
            $url = new moodle_url('/grade/report/index.php', array('id' => $courseid));
            $table->data[] = array(html_writer::link($url, $course->fullname));
        }
        echo html_writer::table($table);
    }