Convert table cells to text-boxes with JQuery

Answer 1

You don't even need Javascript/jQuery:

    <table>
        <tr>
            <td><input type="text" value="My Thing"></td>
        </tr>
    </table>
input {
 border:none;

}
input:active {
    border:1px solid #000;
}

...just use CSS to style the input to look like a span.

Answer 2

$('#editParamValues').click(function () {
    $('tr td:nth-child(3)').each(function () {
        var html = $(this).html();
        var input = $('<input type="text" />');
        input.val(html);
        $(this).html(input);
    });
});