An example of tracking distance traveled and translating to game points. Untested.

DistancePoints.cs

using UnityEngine;
using System.Collections;


public class DistancePoints : MonoBehaviour
{
	public float pointsPerUnit = 1.0f;
	
	
	private Vector3 lastPosition;
	private float measuredDistance;
	
	
	void Start ()
	{
		lastPosition = transform.position;
		measuredDistance = 0.0f;
	}
	
	
	void Update ()
	{
		measuredDistance += (transform.position - lastPosition).magnitude;
		lastPosition = transform.position;
	}
	
	
	public float Points
	{
		get
		{
			return measuredDistance * pointsPerUnit;
		}
	}
}