It behaves in the way that was instructed by the code. You have mixed the 2 div's in one function and attached a second click events to each of them. The result is all mixed up. I have cleaned it up, take a look:
var staff = $("#stuff");
var staff1 = $("#stuff1");
var staff2 = $("#stuff2");
var staff_2 = $("#stuff_2");
staff1.hide();
staff_2.hide();
var toggleStuff = function(event){
staff1.toggle('slow');
}
var toggleStuff2 = function(event){
staff_2.toggle('slow');
}
$("#unbind").click(function(){
staff.unbind('click');
staff2.unbind('click');
});
$("#bind").click(function(){
staff.bind('click',toggleStuff);
staff2.bind('click',toggleStuff2);
});
jsfiddle[
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