I need help with a click to destroy game

I have no clue what I am doing, and need help to try and make a simple click and destroy game for my coursework. I have gotten as far as adding 2d coliders to my objects and a simple script (that is bellow) that makes the objects disappear with one click.

How do I make it so the object takes multiple clicks to destroy?

using UnityEngine;
using System.Collections;

public class Destroy : MonoBehaviour {

void OnMouseDown(){
Destroy(gameObject);
}

}

At the moment you are destroying the object as soon as the user clicks it.

Instead you could have an int as a member of your class that counts how many times it has been clicked, and when it goes over a certain amount then it gets destroyed.

Maybe something like this:

public class Destroy : MonoBehaviour 
{
    public int NumberOfClicksToDestroy = 3; // set this here or in Unity

    // a counter for how many times we have been clicked
    private int ClicksCount;

    void OnMouseDown()
    {
        // they clicks this object, increase its click count
        ClicksCount++;

        // if this has been clicked enough times, destroy it
        if (ClicksCount > NumberOfClicksToDestroy)
        {
            Destroy(gameObject); 
        }
    }
}