Sessile oak acorns

Hi
I collected a handful of acorns from a ancient oak forest I am pretty sure it's sessile oak , 4 of the acorns have started to produce roots , should I leave then out all winter our bring them in, I fear if they sprout leaves to soon and they will die as my garden is exposed to the elements and the forest I got them in they grow in a valley protected from the worst weather, if they have rooted could I put them on a window sile indoors and grow them on to start coming in to leaf over winter ?

 

I'd leave them outside they often make a root now but under normal conditions they don't grow a shoot until spring.