Class using a loop to target mc's on stage

programming flash
1

ive been wrestling with this for the whole day, if anyone can lend a hand
i have 3 check box’s and input text fields on stage that i would like to null out using the reset button
however i seem to be targeting the objects incorrectly as i am getting this error:

Error #1009: Cannot access a property or method of a null object reference.


package
{ 
    import flash.display.*;
    import flash.events.MouseEvent;
	import flash.events.Event;
    import flash.text.TextField

    public class Main extends MovieClip
    {
		private var aCheckBox:Array;
		private var aTextInput:Array;
		
        public function Main():void
		{
            init();
        }
		
        private function init():void 
		{
			bReset.buttonMode = true;
			bReset.addEventListener(MouseEvent.CLICK, resetHandler, false, 0, true);
		}
		
		private function resetHandler(e:MouseEvent):void 
		{
			aCheckBox = [];
			var cb:MovieClip;
			for(var i:int=0;i < 3; i++)	
			{
				cb = getChildByName("cb" + (i + 1)) as MovieClip;
				aCheckBox.push(cb);
				aCheckBox*.selected = false;
			}
			
			aTextInput = [];
			var ti:MovieClip;
			for(var j:int=0;j < 3; j++)
			{
				ti = getChildByName("ti" + (j + 1)) as MovieClip;
				aTextInput.push(ti);
				aTextInput[j].text  = "";
			}
			
		}
    }
}