If you haven't learned how to speak up before you get to a college ethics class, I honestly question whether you ever will. Normally this sort of principle is drilled into people at a very young age. If it doesn't stick, I don't think a professor telling you to read Kant or Singer is going to do any good.
And you don't, or shouldn't, need an ethics course to tell you that minor deviations from the plan can have unintended consequences that might have ethical implications. Take taxi drivers for instance, a minor shortcut over a sidewalk could have lethal consequences; do we expect taxi drivers to know this already without having taken an ethics course in college? Of course.
Honestly I was thinking of the kind of 1 hour "course" that college students and employees get mandated once a year. Those are chock full of useful information and tips. Probably a big change from semester long for-credit college "courses".
Many people learn early in life that to speak up is to get shut down. This can be combated later in life with good examples and policies.
And you don't, or shouldn't, need an ethics course to tell you that minor deviations from the plan can have unintended consequences that might have ethical implications. Take taxi drivers for instance, a minor shortcut over a sidewalk could have lethal consequences; do we expect taxi drivers to know this already without having taken an ethics course in college? Of course.