diff --git a/src/game/mouse/one_to_fifty/chocoball.js b/src/game/mouse/one_to_fifty/chocoball.js
index de6cee1..9583021 100644
--- a/src/game/mouse/one_to_fifty/chocoball.js
+++ b/src/game/mouse/one_to_fifty/chocoball.js
@@ -1,12 +1,24 @@
 // Chocoball.prototype = Object.create(Phaser.Sprite.prototype);
-// Chocoball.constructor = Chocoball;
-
-function Chocoball(index) {
-	this.isActivated = false;
+Chocoball.constructor = Chocoball;
 
+function Chocoball(index, onClickHandler) {
+	this.index = index;
 	this.row = Math.floor(index / 5);
 	this.col = index % 5;
 
+	this.onClickHandler = onClickHandler;
+
+	this.initVariables();
+	this.drawChocoball();
+
+	this.setActive(true);
+}
+
+Chocoball.prototype.initVariables = function(textContent) {
+	this.isActivated = false;
+}
+
+Chocoball.prototype.drawChocoball = function() {
 	var x = 200 + this.col * 100;
 	var y = 200 + this.row * 100;
 	this.body = game.add.sprite(x, y, 'choco_body');
@@ -14,19 +26,16 @@ function Chocoball(index) {
 	this.body.anchor.set(0.5);
 	this.body.tint = 0xff0000;
 
-	this.gloss = game.add.sprite(x, y, 'choco_gloss');
-	this.gloss.scale.set(1);
-	this.gloss.anchor.set(0.5);
+	this.body.inputEnabled = true;
+	this.body.events.onInputDown.add(this.onClick, this);
+
 
 	this.number = this.makeNumber("50");
 	this.body.addChild(this.number);
 
-	// game.add.existing(this);
-	// game.physics.arcade.enable(this);
-
-	// this.halfWidth = this.width / 2;
-
-	this.setActive(true);
+	this.gloss = game.add.sprite(x, y, 'choco_gloss');
+	this.gloss.scale.set(1);
+	this.gloss.anchor.set(0.5);
 }
 
 Chocoball.prototype.makeNumber = function(textContent) {
@@ -49,6 +58,12 @@ Chocoball.prototype.setActive = function(isActivated) {
 	this.isActivated = isActivated;
 }
 
+Chocoball.prototype.onClick = function() {
+	if(typeof this.onClickHandler !== "undefined")
+		this.onClickHandler(this);
+}
+
+
 Chocoball.loadResources = function() {
 	game.load.image('choco_gloss', '../../../resources/image/object/one_to_fifty/choco_gloss.png');
 	game.load.image('choco_body', '../../../resources/image/object/one_to_fifty/choco_body.png');
diff --git a/src/game/mouse/one_to_fifty/game.js b/src/game/mouse/one_to_fifty/game.js
index 8f3a857..4865d48 100644
--- a/src/game/mouse/one_to_fifty/game.js
+++ b/src/game/mouse/one_to_fifty/game.js
@@ -4,8 +4,6 @@ var Game = {
 		this.dbConnectManager = new DBConnectManager();
 		sessionStorageManager.setRecord(0);
 
-		this.game.stage.backgroundColor = "#000000";	// '#4d4d4d';
-
 		sessionStorageManager.setIsNewAppHighestRecord(false);
 
 		var experienceAppTimer = new ExperienceAppTimer();
@@ -22,28 +20,19 @@ var Game = {
 			"1 to 50"	// callerClassName
 		);
 
+		// game stage
+		game.stage.backgroundColor = '#4d4d4d';
+
 		// top ui
 		var screenTopUI = new ScreenTopUI();
 		screenTopUI.makeBackButton( (function() { this.back(); }).bind(this) );
 		screenTopUI.makeFullScreenButton();
-
 		this.stopWatch = new StopWatch(game);
 
 
-		this.chocoballs = new Array();
-		for(var i = 0; i < 25; i++) {
-			var chocoball = new Chocoball(i);
-			chocoball.setNumber(i);
-			this.chocoballs.push(chocoball);
-		}
-
-
+		// init game elements
 		this.initVariables();
 
-		// game stage
-		game.stage.backgroundColor = '#4d4d4d';
-		graphics = game.add.graphics(0, 0);
-
 
 		// bottom ui
 		var screenBottomUI = new ScreenBottomUI();
@@ -57,6 +46,12 @@ var Game = {
 	},
 
 	initVariables: function() {
+		this.chocoballs = new Array();
+		for(var i = 0; i < 25; i++) {
+			var chocoball = new Chocoball(i, this.onClickChocoball);
+			chocoball.setNumber(i);
+			this.chocoballs.push(chocoball);
+		}
 	},
 
 	back: function() {
@@ -65,6 +60,11 @@ var Game = {
 	},
 
 
+	onClickChocoball: function(chocoball) {
+		console.log(chocoball.index);
+	},
+
+
 	startGame: function() {
 		this.stopWatch.start();
 	},