I believe I've read online that they don't need to be stratified if planted fresh. They won't grow a shoot until after a 'winter' period. My neighbour (who does a lot of work with native species) told me that squirrels will dig up seedlings because the acorn remains underground for some time after the sapling has appeared. You will want to cover with a wire cage or something to protect the sapling (I use wire garbage cans from the dollar store with a brick on top). I would say planting outside is the easiest way to go. If you must use pots, use DEEP pots to accommodate the long roots.

Thanks. That's what I thought. Hopefully next year we will have more oaks! Marg

I often find sprouted acorns in my flower beds in the Spring. Assume squirrels have hidden then in the soft earth in the Fall, so I'd also agree outside would be easiest.