alt Hacker Newscounterpoint: it doesn't matter, since you need to learn relevant boiling/freezing temperatures on both scales anyway.
As a european: F is the only american system that is easy to use and reason with (considering its 0-100 range is spanning the "doable" temp range of too-cold to too-hot), unlike other imperial systems for lengths and whatnot.
I would argue feet and inches are pretty good too, since there’s a foot on your body, and a thumb, too, for inches.
Weight, mass and considerable distances, I’ll grant you, though.