How to pass data in $.post jquery to MVC Action method

Question

I am trying to pass data to my controller action Method by using JQuery .$Post method. I have tried multiple ways to pass data but wasn't able to receive any data from the ajax $.post() method.

Here is my script

$.post("/Home/ListChild/", {"259"}, function (data, status) {
    for (var i = 0; i < data.length; i++) {
        remoteData.push({ firstName: data[i].firstName, lastName: data[i].lastName });
    }
    var template = kendo.template($("#javascriptTemplate").html());
    var result = template(remoteData);
    wnd.content(result);
    wnd.center().open();
});

Here is my controller method

public ActionResult ListChild(String userId)
{
    Debug.WriteLine("Passed Value: "+userId);
    return view();
}