Add and remove class in loop using jquery

setInterval(function(){ 
   $('#topcontrol img').toggleClass('wiggle');  
   setTimeout(function(){
     $('#topcontrol img').toggleClass('wiggle');  
   },500);
},1000);

Add class one by one using jquery

$("ul li").on('click' , function () {
  setInterval(function(){
    var el = $('.main_div');
      var index = 0;
        var timer = window.setInterval(function(){
          if  (index < el.length) {
            el.eq(index++).addClass('highlighted');
          } else {
          window.clearInterval(timer);
        }
    }, 1000);
  }, 1);
});

Add class on scroll using jquery

function isScrolledIntoView(elem) {
  var docViewTop = $(window).scrollTop();
  var docViewBottom = docViewTop + $(window).height();

  var elemTop = $(elem).offset().top + 100;
  var elemBottom = elemTop + $(elem).height();

  return ((elemBottom <= docViewBottom) && (elemTop >= docViewTop));
}

$(window).on('scroll', function() {
  $("div").each(function() {
    if (isScrolledIntoView($(this))) {
      $(this).addClass("classname");
    }
  });
});