JSFiddle - React, Tailwind, and code Playground

HTML

<div class="round">
    <ins class="">&nbsp;</ins><a href="#"><ins class="jstree-checkbox">&nbsp;</ins><ins class="jstree-icon">&nbsp;</ins>
                                        School</a><ul style="">
                                            
                                            <li id="2" class="jstree-last jstree-leaf jstree-checked"><ins class="">&nbsp;</ins><a href="#"><ins class="jstree-checkbox">&nbsp;</ins><ins class="jstree-icon">&nbsp;</ins>
                                                school principal</a></li>
                                            
                          </ul>
        </div>

JavaScript

alert($('div.round').children('.jstree-leaf').length);