Need to get rid of persistent images created with as3 - pls help

Question

I have used the following as3 code, courtesy of Jody Hall at theflashconnection.com .  It's a drag and drop that works great. Problem is the drag and drop images persist when I move on to other frames. How do I clear the images when finished so they don't appear in subsequent frames? Thank you in advance.
import flash.events.MouseEvent;
import flash.display.MovieClip;
import flash.media.Sound;
import flash.media.SoundChannel;
var sndExplode:explode_sound;
var sndExplodeChannel:SoundChannel;
var dragArray:Array = [host1, agent1, physical1, social1, host2, agent2, physical2, social2, host3, agent3, physical3, social3];
var matchArray:Array = [targethost1, targetagent1, targetphysical1, targetsocial1, targethost2, targetagent2, targetphysical2, targetsocial2, targethost3, targetagent3, targetphysical3, targetsocial3];
var currentClip:MovieClip;
var startX:Number;
var startY:Number;
for(var i:int = 0; i < dragArray.length; i++) {
    dragArray[i].buttonMode = true;
    dragArray[i].addEventListener(MouseEvent.MOUSE_DOWN, item_onMouseDown);
    matchArray[i].alpha = 0.2;
function item_onMouseDown(event:MouseEvent):void {
    currentClip = MovieClip(event.currentTarget);
    startX = currentClip.x;
    startY = currentClip.y;
    addChild(currentClip); //bring to the front
    currentClip.startDrag();
    stage.addEventListener(MouseEvent.MOUSE_UP, stage_onMouseUp);
function stage_onMouseUp(event:MouseEvent):void {
    stage.removeEventListener(MouseEvent.MOUSE_UP, stage_onMouseUp);
    currentClip.stopDrag();
    var index:int = dragArray.indexOf(currentClip);
    var matchClip:MovieClip = MovieClip(matchArray[index]);
    if(matchClip.hitTestPoint(currentClip.x, currentClip.y, true)) {
        //a match was made! position the clip on the matching clip:
        currentClip.x = matchClip.x;
        currentClip.y = matchClip.y;
        //make it not draggable anymore:
        currentClip.removeEventListener(MouseEvent.MOUSE_DOWN, item_onMouseDown);
        currentClip.buttonMode = false;
        sndExplode=new explode_sound();
        sndExplodeChannel=sndExplode.play();
    } else {
        //match was not made, so send the clip back where it started:
        currentClip.x = startX;
        currentClip.y = startY;
DRAG AND DROP (I JUST DID THE LAST FOUR FOR THIS EXAMPLE)
MOVING ON TO NEXT FRAME, YOU STILL SEE THE RECTANGLES.

Answer 1

Thank you SO muchNed Murphy
I'm a newbie to AS3 and I was trying to figure it out for past 2 weeks that why did swapChildren or setChildIndex or addChild, all of these made my Target Movieclip remain/duplicate/persist on the stage even after the layer containing the Target Movieclip has blank keyframes. I surfed so many forums and tutorials for the answer but turns out it was my lack of knowledge of basic concepts. I remember checking out this specific forum as well past week but due to it being "Not Answered" I skipped it. This should be marked as a "Correct Answer", The Empty MovieClip did the trick!
I needed this solution for a Drag and Drop game, so that the current item that is being dragged is above all other graphic layers. And when all items are dropped on their correct targets, there is gotoAndPlay to Success frame label.
I created a movieclip on the top layer with the same dimensions as the stage and put it at x=0 y=0 position. Instance name: emptymc
And deleted the emptymc from the timeline during the Success frame label.
Here is some code I used,
1. MovieClip.prototype.bringToFront = function():void {
   emptymc.addChild(this);
2.  function startDragging(event:MouseEvent):void {
  event.currentTarget.startDrag();
  event.currentTarget.bringToFront();
I didn't know how to put the addChild and refer to the currentTarget in the startDragging function itself, for example
emptymc.addChild(event.currentTarget);
- This one didn't work inside the startDragging function "emptymc.addChild(this); "
Is there a correct way I could have done it properly?
Thanks,
Dipak.