I seriously doubt any judge is going to uphold a ticket for a parent teaching their kid to drive, especially if the parent is ensuring the area is safe.
Get a Learners Permit, and you're safe. I'm a LEO, if your on private property and have permission to drive on it, your safe. On back roads, your screwed.
It'll depend on the officer if he wants to be a dick.
My uncle (closest thing I had to a grandpa) first started teaching me to drive in the hay fields when I was 5 or 6. Obviously not on my own but under close supervision. Those were the days.