Change Sprite within an image component with a script

I am using javascript to create a script to change a sprite in a UI image box for a tic tac toe game. My current code is just to change back and forth between two sprites both located in Assets/pictures/sprites folder. Here is my code:

#pragma strict
var Image : UnityEngine.UI.Image;
var flip = true;

function Start () {
}

function Update () {
	if(flip){
		flip = false;
		Image.sprite = Resources.Load ("o_green") as Sprite;
		//Debug.LogWarning(flip);
	} 
	else {
		flip = true;
		Image.sprite = Resources.Load ("o_red") as Sprite;
		//Debug.LogWarning(flip);
	}
}

Here is my setup in the Unity editor:

41749-topright.png

I have tried changing the path to “pictures/sprites/o_red” but still it does not change the sprite when running the game. Am I getting the path wrong? Or am I approaching this the wrong way?

Resources.Load can only load assets that are placed inside a folder named Resources. (Or from subfolders inside this one)
Move your sprites inside this folder then you can load them from there.
for example if the image is at “Resources/pictures/sprites/o_red.png” the argument should be
“pictures\sprites\o_red”