Making a button disappear Permanetely....

New to Flash...I am making an interactive E Learning Module. I created a menu with 4 buttons. Each button takes you through a different section of the module. What i am trying to accomplish is a notification that you have completed a section by changing the Menu Button to be grey. I created 2 buttons (one in color and one in Black and White). I placed the colored button on top of the Black and white button and then wrote this code. The problem is that even though the code works it resets every time you return to the Menu. How do i make it permanent (until the module is reloaded)

// Amp_Btn1 Click function

function mouseHandler(event:MouseEvent):void

{

  //stop listening for clicks

  Amp_btn1.removeEventListener(MouseEvent.CLICK, mouseHandler);

  //make button invisible

  Amp_btn1.visible = false

}