I'm probably too much of a stickler for high school. If I had students try to trick me with T/F confusion I'd immediately announce a "round towards the wrong a

I'm probably too much of a stickler for high school. If I had students try to trick me with T/F confusion I'd immediately announce a "round towards the wrong answer" policy and watch 'em tidy up right quick. Some european students threw me when I started grading in university though. Their 1s look like my 7s as you describe, but they cross their 7s to disambiguate.