Modify Variables in a Script from another Script?

I have two scripts in my game, a Grid Script and a Properties Script. The Grid creates an X by Y grid of cubes where each individual cube has a “Properties” Script. In properties I have a height variable that I would like the Grid Script to set. Basically I have:

for (int i = 0; i < gridArr.GetLength(0); i++){
			for (int k = 0; k < gridArr.GetLength(1); k++){
					if (!(GameObject.Find(i+","+k) != null)) {
					GameObject obj = Instantiate(fill, new Vector3(i, 0, k),
						Quaternion.identity) as GameObject; = (i+","+k);
					gridArr[i,k] = obj;

In the Grid Script and then I have:

public class Properties : MonoBehaviour {		
	public int height;

In the Properties class. How would I go about modifying the height variable in this Class?