CourseWork/resources/views/includes/header.blade.php

<div class="container">
    <header class="d-flex justify-content-center py-3">
        <ul class="nav nav-pills">
            <li class="nav-item"><a href="{{ route('grades.index') }}" class="nav-link @if(request()->is('grades*')) active @endif" aria-current="page">Классы</a></li>
            <li class="nav-item"><a href="{{ route('subjects.index') }}" class="nav-link @if(request()->is('subjects*')) active @endif">Предметы</a>
            <li class="nav-item"><a href="{{ route('students.index') }}" class="nav-link @if(request()->is('students*')) active @endif">Ученики</a></li>
            <li class="nav-item"><a href="{{ route('teachers.index') }}" class="nav-link @if(request()->is('teachers*')) active @endif">Учителя</a></li>
        </ul>
    </header>
</div>