Unity Projects: 2D Platformer save score into next level

[tolgaclk]

I have some problem , I copied Unity Projects: 2D Platformer game, and created twice as a second level .and I tried to move second level but I could do save the score . How can I do that?

using UnityEngine;
using System.Collections;

public class Score : MonoBehaviour
{
public int score = 0; // The player’s score.

private PlayerControl playerControl;	// Reference to the player control script.
private int previousScore = 0;			// The score in the previous frame.

// private float _score = 0;

void Awake ()
{
	// Setting up the reference.
	playerControl = GameObject.FindGameObjectWithTag("Player").GetComponent<PlayerControl>();
	//Write the score in the GUI text
	//previousScore = _score;

 	DontDestroyOnLoad(gameObject);
}

void Update ()
{
	 
	// Set the score text.
	guiText.text = "Score: " + score;

	// If the score has changed...
	if(previousScore != score)
		// ... play a taunt.
		playerControl.StartCoroutine(playerControl.Taunt());
	 
	if (score >= 500) {
		 
	 //	PlayerPrefs.SetInt("score", _score);
		Application.LoadLevel("LEVELX");
			}
	// Set the previous score to this frame's score.
 	previousScore = score;
}

}

[tolgaclk]

if (score >= 200) {

Application.LoadLevel ("Level 2");

}