JSFiddle - React, Tailwind, and code Playground

HTML

<legend><b><u>CASUALTIES SUMMARY CHART</u></b></legend>
                                    <table>
                                        <tr>
                                            <td><label for="form">Casualty:</label></td>
                                            <td><select id="myselect" name="myselect">
                                                    <option value="Student">Student</option>
                                                    <option value="Staff">Staff</option>
                                                </select>
                                            </td>
                                        </tr>
									</table>
									<div id="studentForm">
                                        <form id="casualties-Form" name="casualtiesForm" method="post" action="doCasualtiesForm.php">
										<table>
                                            <tr>
                                                <td width="150px"><label for="date">Date:</label></td>
                                                <td><input type="date" id="date" name="Date"/></td>
                                            </tr>
                                            <tr>
                                                <td><label for="time">Time:</label></td>
                                                <td><input type="time" id="time" name="Time"/></td>
                                            </tr>
                                            <tr>
                                                <td>ID:</td>
                                                <td><input type="text" name="ID"></td>
                                            </tr>
                                            <tr>
                                                <td><label for="School">School</label></td>
                                                <td><select>
                                                        <optgroup label="ss" name="School">...

CSS

#staffForm {
    display: none;
}

JavaScript

$(document).ready(function(){
    $('#myselect').change(function(){
            if ($(this).val() === "Student") {
            		$('#staffForm').hide();
                    $('#studentForm').show();
            } else {
                    $('#studentForm').hide();
            		$('#staffForm').show();
            }
    });
});